THE  LIBRARY 

OF 

THE  UNIVERSITY 
OF  CALIFORNIA 

LOS  ANGELES 


PLASTICS 


PLASTIC    FILLI 


AS  PERTAINING  TO  THE 


FILLING  OF   ALL   CAVITIES  OF   DECAY   IX   TEET 
BELOW   MEDIUM    IX    STRUCTURE, 


Q,  J.  GOLDIE, 
14*  UP.  WflMPOLE  8T, 


DIFFICULT  AND  INACCESSIBLE  CAVITIES 
IN  TEETH   OF   ALL   GRADES  OF  STRUCTURE. 


Q^l  BY 

J.  FOSTER  FLAGG,  D.D.S. ; 

PROFESSOR  OF   DENTAL  PATHOLOGY   AND  THERAPEUTICS  IN 
PHILADELPHIA  DENTAL  COLLEGE. 


WI TH   ILL  US  T  RAT  10  NS . 


PHILADELPHIA: 

PRESLEY    BLAKISTON, 

1012  WALNUT   STREET. 

1881. 


COPYRIGHT. 
J.  FOSTER  FLAGG. 

1881. 

ALL  RIGHTS  RESERVRD. 


STEREOTYPED    BY    .1.  F.UiAN    ,v    SON,   PHILADELPHIA. 
I'llINTED  BY  SHERMAN  A  CO. 


500 


TO 

THE  SCIENTIFIC,  METALLURGIC,  AND  DENTAL  SECTIONS 

OF  THE 

"NEW   DEPARTURE  CORPS/- 
THIS MONOGRAPH 

IS   INSCRIBED,   AS   A  TESTIMONIAL 
OF   INDIVIDUAL  INDEBTEDNESS, 

OF  SINCERE  RESPECT, 
AND  OF  KIND  REGARD. 


PREFATORY. 


TN  explanation  of  the  occasionally  desultory  arrangement 
of  the  matter  in  these  pages,  and  of  some  of  the  peculi- 
arities of  composition,  I  would  say  that  the  "  Articles  "  were 
originally  intended  for  magazine  contributions,  but,  in  evo- 
lution, the  statements  which  I  decided  to  make,  the  infor- 
mation which  I  desired  to  give,  and  the  deductions  which 
would  necessarily  have  to  be  drawn,  were  such  as  I  could 
not  ask  any  magazine  of  extensive  circulation,  with  exten- 
sive business  interests,  to  publish.  I  have  therefore  con- 
cluded to  offer  them  in  this  form  that  I  might,  for  the 
good  of  my  profession  —  as  I  hope  and  as  I  trust  —  dis- 
seminate, in  all  its  integrity,  the  results  of  that  work  which 
has  been  done  by  the  "New  Departure  Corps"  under  its 
motto.  "  Truth,  without  fear  and  without  favor.'' 

J.  FOSTEE  FLAGG. 

PHILADELPHIA,  106  N.  llth  St. 


CONTENTS. 


INTRODUCTORY. 

PAGE 

Difference  in  basal  principles  which  exists  between  the  Schools  of  Gold  and 

Plastic  Dentistry • 11-18 

ARTICLE  I. 

PLASTIC  FILLING. 
History  of  the  work  upon  the  "  Systematic  Development  of  Plastic  Filling  "  19-23 

ARTICLE  II. 

AMALGAM. 

Silver  Paste  ;  Royal  Mineral  Succedaneum ;  Action  of  the  American  Society 

of  Dental  Surgeons;  Dissolution  of  that  Association         .        .        .        .24-29 

ARTICLE  III. 

.  1 M.  1 L  GA  M.  -  Continued. 

Facts  worthy  of  consideration ;  Prof.  Elisha  Townsend's  sanction  of  amal- 
gam ;  His  acceptance  and  advocacy  of  proposed  improvements  in  alloy 
and  making  of  amalgam ;  Action  of  the  representative  men  of  the  pro- 
fession ;  Professor  Townsend's  "  recantation ; "  The  three  basal  positions 
in  connection  with  amalgam  which  decided  me  in  continuing  work,  not- 
withstanding my  leader's  "  recantation ; "  Conclusions  reached  by  five 
years  of  experiment'  and  observation 29-36 

ARTICLE  IV. 

A  MA  L  GA  M.— Contin  ued. 

From  1861  to  1875  ;  Change  of  formula ;  Adoption  of  "  lining;  "  December, 
1874,  Meeting  of  New  York  Odontological  Society ;  Metallurgic  associ- 
ation with  Messrs.  Du  Bois  and  Eckfeldt;  Comments  upon  paper  of  Pro- 
fessor Hitchcock ;  Comparison  of  Analyses  of  Amalgam  Alloys ;  Remarks 
on  "  Gold  and  Platina  "  alloys ;  Remarks  on  "  advanced  collegiate  instruc- 
tion"    37-42 

ARTICLE  V. 

ATTRIBUTES  OF  METALS    USED  FOR  AMALGAM  ALLOYS. 

Definitions  of  "  alloy  "  and  "  amalgam  ;  "  Theory  of  the  formation  of  amal- 
sanis;  Metiils  used  in  amalgam  alloys;  Silver;  Tin;  Copper;  Gold; 
Antimony;  Zinc;  Cadmium;  Platinum  .  .  .  •  .  .  .  .  43-60 


CONTENTS.  Vll 

ARTICLE  VI. 

THE  MAKING  OF  AMALGAM  ALLOYS. 

"Accepted"  methods  given  by  different  instructors;  The  completely  differ- 
ent method  of  the  "  New  Departure"  metal  workers;  Cutting  of  alloy 
into  "  grains,"  "  filings,"  or  "  a  kind  of  powder ;  "  Inferiority  of"  fresh  " 
cut  alloy;  Superiority  of  "aged"  alloy  filings;  Qualitative  Testing  of 
Amalgam  Alloys 61-66 

ARTICLE  VII. 

TESTS  FOR  AMALGAM. 

Quality  test ;  Shrinkage  test ;  Color  test ;  Edge-strength  test ;  Tooth-con- 
serving test 67-80 

ARTICLE  VIII. 

PREPARATION  OF  CAVITIES. 

Comparison  of  preparations  for  gold,  with  preparations  for  amalgam  ;  Effect 

of  amalgam  upon  contiguous  dentine 80-84 

ARTICLE  IX. 

THE  MAKING  OF  AMALGAM. 

Former  methods  ;  Remarks  on  alcoholic  "  washing  ;  "  Mortar-make ; 
Weighing  for  proportions;  Ground -glass  mortar  and  pestle;  The 
method  of  rubbing ;  Method  of  kneading ;  The  forming  of  a  "  button ; "  84-92 

ARTICLE  X. 

INSTRUMENTS  FOR  THE  INSERTION  OF  AMALGAM  FILLINGS. 

Description  of  instruments ;  Round  ends  ;  Flat  ends ;  Trimmers  or  Sepa- 
rators; Spatula;  Elliott's  "  Loadstone  "  amalgam-carrier  and  plugger; 
Elliott's  amalgam  carrier ;  Chase's  amalgam  carrier ;  Fry's  amalgam 
carrier;  Mullett's  "  Amalgam  Director;"  Curious  and  useless  appli- 
ances .  92-99 

ARTICLE  XL 

THE  INSERTION  OF  AMALGAM  FILLINGS. 

Necessity  for  acquirement  of  manipulation  by  nearly  every  dentist,  from 
the  marked  difference  in  physical  characteristics  between  "accepted" 
amalgams,  and  those  offered  by  the  "  Xew  Departure  : "  Present  di- 
vision of  amalgams;  Submarine;  Usual;  Contouring;  Front  Tooth; 
Facing;  Manipulations  for  insertion  of  amalgam  mass;  Wafering; 
Shaping;  Smoothing;  Finishing;  Whitening;  Subsequent  burnish- 
ing, if  indicated  ;  Remarks  upon  burnishing  the  edges  of  partially-set 
amalgam  fillings 99-107 


Viii  CONTENTS. 

ARTICLE  XII. 

GENERAL  CONSIDERATIONS  PERTAINING  TO  AMALGAM. 

1.  Local  effects;  2.  Systemic  effects ;  3.  Possibilities;  FIRST.  Local  Effects.— 
Discoloration  of  filling  and  tooth  ;  Induction  of  galvanic  electricity  by 
contact  with  other  metal ;  Shock  ;  Metallic  salivation;  Bad  taste;  Irri- 
tation of  fauces,  throat,  and  larynx  ;  Pulp-devitalization ;  Periodon- 
titis ;  Alveolar  abscess  ;  Exostosis ;  Necrosis. 

SECOND.  Systemic  Effects. — Proceedings  of  Pennsylvania  Association 
of  Dental  Surgeons,  April,  1861 ;  Testimony  of  members  adverse  to 
mercurial  ptyalism,  mercurial  necrosis,  etc. ;  My  own  opinion  regard- 
ing mercurialization  from  amalgam  fillings. 

THIRD.  Possibilities. — Possibilities  of  amalgam  are  greater  than  those 
of  all  other  filling  materials  combined ;  Comparison  of  the  working  of 
gold  with  that  of  amalgam;  Ordinary  cavities;  Large  cavities;  Enor- 
mous cavities;  Entire  crowns;  Attaching  gold  crowns  by  amalgam; 
Replacing  natural  crowns ;  Attaching  natural  crowns ;  Pivoting  teeth  ; 
Bonwill  pivot;  Gates  Pivot;  Flagg  pivot;  '-Guarding"  or  repairing 
gold  fillings,  and  refilling  cavities  from  which  gold  fillings  have  been 
lost,  in  teeth  which  still  contain  gold  fillings;  Bi-metallic  fillings; 
Therapeutic  value  of  these;  Amalgam  teeth  on  gold  plates;  Fractures 
of  teeth  from  fillings  either  of  gold  or  amalgam ;  Split  teeth ;  Per- 
forated teeth  ;  Loose  and  divided  roots  ;  The  dividing  line- between  the 
impossibilities  of  gold  work  and  the  continued  easy  possibilities  of 
amalgam  work ;  The  comfort  from  plastics 107-141 

ARTICLE  XIII. 

GUTTA-PERCHA. 

Hill's  stopping ;  Gutta-percha  and  Oxide  of  Zinc  Stoppings;  Leakage  of 
gutta-percha  fillings;  "Low-heat"  gutta-percha;  "Medium  heat;" 
"High  heat;"  Red  base-plate ;  Oil-pad;  Modes  of  heating  gutta-percha 
filling  materials ;  Methods  of  heating  instruments ;  Considerations  per- 
taining to  preparation  of  cavities  for  gutta-percha  fillings;  The  intro- 
duction of  fillings  ;  Finishing  fillings ;  Tests  for  gutta-percha  stopping  ; 
Heat-test;  Fire-test;  The  making  of  gutta-percha  stopping;  Dura- 
bility of  gutta-percha  fillings;  Cavities  in  which  the  use  of  gutta- 
percha  alone  is  indicated  ;  The  varied  uses  of  gutta-percha  stoppings  141-150 

ARTICLE  XIV. 

OXY-CHLORIDE  OF  ZINC. 

Sorel  cement;  Uses  of  oxy-chloridc  of  zinc;  "Talcing"  fillings;  Oxy- 
chloride  not  a  filling  material;  Oxy-chloride  a  complete  "liner;" 
Failure  of  oxy-chloride  from  attrition  ;  Failure  of  oxy-chloride  from 
cervical  disintegration;  The  making  of  oxy-chloride  powder;  The 
making  of  the  fluid  ;  The  mixing  of  the  materials  for  filling;  Method 
of  lining  cavities ;  Results  attained  by  the  use  of  oxy-chloride ;  Re- 
marks in  relation  to  "  combination  "  fillings  ;  "  Whitening"  teeth  by 
the  use  of  oxy-chloride  151-160 


CONTEXTS.  IX 

ARTICLE  XV. 

OXY-SULPHATE  OF  ZINC. 

Not  a  filling  material,  but  eminently  useful  as  an  adjunct  to  plastic  fillings ; 
The  making  of  oxy-sulphate  powder ;  The  making  of  oxy-sulphate 
fluid ;  Oxy-sulphate  as  a  pulp-capper ;  Its  mixing  ;  Capping  by  spat- 
ula placing ;  Capping  by  pellet  placing 160-162 

ARTICLE  XVI. 

ZINC-PHOSPHA  TE. 

Ostermann's  formula;  The  sine-phosphates  of  the  present;  The  oxy-phos- 
phates ;  The  making  of  zinc-phosphate  powder;  Tests  for  distinguish- 
ing it  from  oxy-phosphate  powder  (calcined  oxide  of  zinc) ;  Remarks 
on  oxy-phosphate  and  zinc-phosphate  fluids,  syrups,  and  crystals;  Mix- 
ing zinc-phosphate;  Working  tests  for  grading  a  "  good  "  zinc-phos- 
phate material ;  Working  tests  for  grading  a  "  poor  "  zinc-phosphate ; 
Directions  for  using  zinc-phosphate;  Varnish  recipes;  Final  manip- 
ulative suggestions;  Conclusions  as  to  value  of  zinc-phosphate  cement  162-174 


ARTICLE   XVII. 

TEMPORARY  STOPPING. 


Directions  for  making 


174 


ARTICLE   XVIII. 

TECHNICALITIES. 


Ageing     . 
Bulging    . 
Buffering  :  Capping  ; 
ing        ... 
Crevicing 
Domeing;  Facing   . 
Frotting   . 
Guarding 
Heating    . 
Lining 

CONCLUSION 

.  175 
.  176 
Cold-Solder- 
.  177 
.  179 
.  180 
.  182 
.  183 
.  189 
.  190 

Mixing     ..... 
Pelleting;  Rubbing 
Setting     .... 

.  191 
.  193 
195 

Softening 

197 

Shrinkage         .... 
Tapping;  Testing    . 
Trimming         .... 
Trunnioning;  Wafering 
Washing  ;  Weighing 
Whitening       .... 

.  198 
.  199 
.  202 
.  203 
.  204 
.  20G 

.  207 

PAGE 

MONOGRAM,  N.  D.  C.    .         .         .         .         .         .         .         .         .  .         .     iii 

MIXER           ...........  opposite     65 

INDEX  MICROMETKR      .........  "          74 

"SHRINKAGE"  MICROSCOPE           .......  "          75 

EDGE-STRENGTH  TESTER  AND  INGOT  MATRIX        ....  "          77 

MORTAR,  PESTLE,  AND  MERCURY  HOLDER      .....  "          90 

AMALGAM  INSTRUMENTS          . "93 

AMALGAM  CARRIERS,  ETC.      ........  "98 

GUTTA-PERCHA  WARMER  AND  TOOL-HEATER         ....  "        144 

GUTTA-PERCHA  HEAT-TESTER        .......  "        147 

FROTTING  TESTER         .........  "         183 

WATERING  PLIERS          .         .  "         204 


PLASTICS 


AND 


PLASTIC    FILLING. 


INTRODUCTORY. 

T)EFORE  entering  upon  considerations  pertaining  to  the  his- 
-D  toric,  analytic,  utilizing,  and  manipulative  detail  of  our 
subject,  I  feel  desirous  that  the  thoughts  of  my  readers  should 
oe  so  directed  as  that  there  shall  be,  at  once,  a  recognition  of 
the  great  fundamental  differences  in  basal  principles  and  prac- 
tice which  exist  between  the  Schools  of  Gold  and  Plastic  Den- 
tistry. 

As  facts  in  relation  to  present  methods  and  results  are  accu- 
mulating, I  am  the  more  impressed  with  the  growing  need  for 
the  uprooting  of  that  tendency  in  dental  teachings  and  practice 
which  has,  thus  far,  resulted  in  such  waste  of  time,  energy, 
strength,  money,  and  teeth,  and  which  still,  in  some  sort,  holds 
sway  at  the  gatherings  of  the  "wise  men." 

The  idea  of  pounding  piece  after  piece  of  gold  into  some 
inaccessible  pocket,  far  below  the  gum,  in  an  "  annex "  to  a 
cavity  -almost  into  the  pulp,  on  the  distal  face  of  a  lower 
molar  of  poor  structure,  and  calling  it  "  the  highest  attain- 
ment of  first-class  dentistry,"  is,  to  me,  something  incompre- 
hensible !  It  is  but  trifling  with  the  dignity,  the  broad  ability, 
the  glorious  possibility,  of  our  profession.  Nor  is  this  an 
overdrawn  picture ;  it  is  precisely  what  is  yet  done  —  done 
"  by  and  with  the  advice  and  consent  of  the  Senate,"  and  it  is 

11  ' 


12  PLASTICS    AND    PLASTIC    FILLING. 

truly  an  imposition  upon  patients  and  upon  the  younger  den- 
tists, inflicted  in  the  name  of  science  and  of  art. 

The  depth  and  the  breadth  of  the  work  to  which  I  have 
been  called  impresses  me  most  earnestly  as  I  view  more  and 
more  clearly  the  vast  difference  between  "  Gold-work,"  regard- 
ing that  as  one  school  of  dentistry,  and  "  Plastics,"  regarding 
that  as  another  school  of  dentistr}^. 

Outwardly,  the  two  schools  are  very  different  even  to  the 
most  casual  observer,  but  in  proportion  as  one  is  educated 
in  both,  this  external  difference  becomes  even  more  tangibly 
apparent ;  the  materials  are  different ;  the  appliances  are  dif- 
ferent; the  methods  are  different;  the  instruments  are  differ- 
ent; the  attempts  are  different;  the  possibilities  are  different, 
and  the  results  are  different. 

The  time  has  gone  by  when  to  this  last  assertion  the  "  gold- 
workers  "  can  say,  with  a  palpably  implied  tone  of  superiority, 
"  Yes,  the  results  are,  indeed,  widely  different,"  for  the  people 
are  trumpeting  loudly  their  stories  of  heart-sickening  failures 
and  wholesale  loss  of  teeth.  The  mouths  of  a  fearful  propor- 
tion of  this  generation  reveal  only  too  glaringly  the  peculiar 
curve  of  "  porcelain  teeth  mounted  on  vulcanite,"  and  the  de- 
mand is  for  something  far  different  from  that  which  has  here- 
tofore been  given  them  as  "  dentistry." 

But  great  as  are  the  external  differences  between  the  "gold- 
workers1  "  practice  of  dentistry  and  its  practice  from  the 
"plastic"  standpoint,  the  internal  differences  are  vastly  greater. 
The  ideas  of  the  two  kinds  of  practice  flow  in  two  channels, 
than  which  no  two  could  be  more  distinct.  The  thoughts 
which  govern  work  in  the  two  kinds  of  practice  are  constantly 
almost  diametrically  antagonistic,  and  are  never,  in  any  degree, 
sympathetic. 

The  minutiae  of  " plastics  "  is  an  unknown  thing  to  the  gold- 
worker.  It  consists  of  special  knowledge  in  regard  to  much 
which  is  only  known  to  him  as  a  mass  of  vague  generalities; 
while  the  "ways  and  means'111  of  the  worker  in  plastics  are 
viewed  askance  by  the  gold-worker  as  a  series  of  shiftless  devices 
promotive  of  slovenly  results. 

The  minutise  of  "  gold-work  "  is  utterly  ignored  by  the  worker 
of  "plastics"  and  for  such  "ways  and  means'1'  as  he  sees  the 


INTRODUCTORY.  13 

gold-worker  resort  to  in  "difficult  cases,"  the  worker  of  plastics 
has  a  shuddering  horror  ! 

The  first  view  of  any  case  in  practice,  as  seen  from  the  two 
standpoints,  is  provocative  of  such  different  impressions  upon 
the  two  practitioners  as  renders  it  impossible  that  the  one 
should  have  any  conception  of  the  effect  made  upon  the  other ; 
and  only  he  who  is  conversant  with  both  schools  can,  in  full 
degree,  appreciate  this. 

Take,  for  instance,  in  a  perfect  arch,  a  lower  second  molar ; 
soft  structure;  largely  decayed  distally  and  buccally;  the  decay 
extending  deep  below  the  gum  in  both  directions  and  running 
out  to  feather-edges ;  with  frail,  overhanging  cavity  walls  rne- 
sially  and  lingually ;  the  pulp  almost  exposed ;  the  patient,  a 
lady  of  nervo-bilious  temperament,  middle-aged,  a  sufferer  from 
congestion  of  the  liver,  and  overtaxed  nervously. 

What  is  the  first  thought  of  the  "  gold-worker  "?  It  is,  How 
shall  I  get  a  good,  solid,  gold  filling  into  this  cavity? 

What  is  the  first  thought  of  the  "worker  in  plastics"?  It 
is,  What  is  it  best  that  I  should  fill  this  cavity  with  ? 

Next  comes  the  cavity  preparation.  The  thoughts  of  the  gold- 
worker  are  concentrated  upon  the  making  of  free  access  for  the 
introduction  and  packing  of  his  gold ;  upon  the  securing  of 
strong,  smooth  edges ;  upon  the  making  of  retaining  points ; 
upon  the  removal  of  all  decay,  except  such  as  would  endanger 
the  pulp,  that  his  gold  may  have  a  solid  foundation  to  rest 
upon,  and  that  he  may  be  able  to  introduce  a  filling  which  will 
not  leak;  upon  the  possibility  of  "capping," — thinking  of  "con- 
duction" of  filling  material, —  and  upon  the  squaring  and  the 
grooving  of  the  walls  at  feather- edges. 

The  thoughts  of  the  worker  in  "plastics"  are  upon  the  con- 
servation of  enamel ;  the  spheroiding  of  cavity  contour ;  the 
conservation  of  decay, — within  the  bounds  of  filling  integrity, — 
hardly  bestowing  a  thought  upon  the  pulp,  and  certainly  no 
thought  upon  pulp  irritation  from  "conduction;"  choosing,  men- 
tally, a  filling  possessed  of  "  edge-strength  "  in  view  of  feather- 
edge  to  cavity;  selecting  his  most  trustworthy  "submarine" 
in  view  of  depth  of  cavity  below  the  gum;  projecting  a  "com- 
bination filling"  which  shall  be  composed  of  four  metal  amal- 
gam—  mercury,  silver,  tin,  and  copper;  five  metal  amalgam  — 


14  PLASTICS    AND     PLASTIC    FILLING. 

mercury,  silver,  tin,  copper,  and  gold.  Good  gutta-perchas, — 
red  or  white. "low  heat"  and  white  "medium  heat," — each  fill- 
ing material  used  in  its  proper  place  for  the  attaining  of  some 
specific  result ;  and  thus,  according  to  his  ideas,  best  securing 
against  recurrence  of  decay ;  best  affording  good  maintenance 
of  color  and  contour  for  resistance  in  mastication;  and  best 
securing  that  uninterrupted  pulp  action  which  shall  not  only 
preserve  the  integrity  of  the  organ,  but  shall  eventuate  in  re- 
calcification  of  the  remaining  substratum  of  decalcified  dentine. 

Next  follows  the  introduction  of  the  filling.  Here  the  seri- 
ous labor  of  the  gold-worker  begins.  He  is  an  earnest,  con- 
scientious man ;  he  is  an  eminently  skilful  manipulator  ;  he 
glories  in  his  work ;  his  whole  thought  must  now  be  concen- 
trated upon  the  introduction  of  his  filling;  any  interference 
with  this  precludes  the  possibility  of  success. 

As  a  necessary  prelude,  the  decayed  tooth  and  the  adjoining- 
teeth  must  be  placed  "under  rubber."  The  work  of  adjusting 
the  rubber-dam,  in  such  a  case  as  this,  is  one  requiring  much 
knowledge,  much  patience,  and  much  dexterity ;  knowledge  of 
fitness  and  quality  of  rubber- dam,  knowledge  of  punches  and 
their  using,  knowledge  of  clamps  and  clamp-forceps ;  patience 
under  difficulty,  patience  oftentimes  under  repeated  tearing 
and  slipping  of  the  dam,  patience  under  remonstrance  at  in- 
fliction, patience  under  failure  until  success  is  attained;  dex- 
terity in  forcing  clamps  below  the  gum,  dexterity  in  passing 
rubber  over  clamps  and  over  and  between  the  teeth,  dexterity 
in  placing  and  securing  retaining  ligatures. 

All  this  work  is  very  exhausting  both  to  patient  and  opera- 
tor; and  it  is,  therefore,  under  conditions  trying  alike  to  mind 
and  body  that  the  difficult  task  of  the  introduction  of  the  fill- 
ing is,  at  last,  commenced. 

Then  comes  a  work  of  hours  —  two,  three,  it  may  be  four  — 
in  such  a  cavity  as  this.  Whether  it  be  of  pellets,  rope,  or  cyl- 
inders ;  whether  it  be  of  soft  gold  or  cohesive ;  whether  it  be 
by  hand-pressure  or  with  mallet, —  automatic,  hand,  engine,  or 
electric, — it  is,  by  any  means,  in  any  'way,  a  famous  piece  of 
work.  It  is  a  work  which  can  be  best  done  by  not  more  than 
one  worker  in  a  thousand ;  a  work  which  can  be  well  done  by 
not  more  than  one  worker  in  a  hundred  ;  a  work  which  is  not 


INTRODUCTORY.  15 

reasonably  -well  done  by  more  than  one  worker  in  ten;  and  yet 
a  work  which  is  attempted  in  gold-ivorking  dentistry  by  nine 
workmen  out  of  ten. 

And  during  all  the  progress  of  this  work,  what  are  the 
thoughts  of  the  gold-worker?  First,  his  thoughts  are  on  the 
choosing  of  his  gold.  Shall  it  be  "Abbey's,"  "Globe,"  or  "Ash- 
mead's"  ?  Shall  it  be  "  Morgan's  "  or  "  Watt's  Crystal "  ?  Next 
his  thoughts  are  on  its  preparation.  He  revels  in  the  beauti- 
ful. All  his  ideas  are  aesthetic.  This  is  the  "power"  of  such 
gold  work ;  its  strength  is  in  its  beauty,  and  in  the  beauty  of 
its  surroundings,  and  it  must  be  recognized  as  possessing  it ; 
so  he  deftly  handles  his  "crystal"  as  he  picks  off'  little  mor- 
sels, or  folds  his  golden  ribbons  and  cuts  them  into  pieces,  or 
inrolls  pellets,  or  twists  sheets  into  ropes,  all  laid  on  skins  of 
kid  or  dropped  on  velvet  cushions. 

This  being  done,  he  thinks  of  final  "  warm-air  "  drying  ;  and 
next  on  the  successful  filling  of  the  first  retaining  point ;  and 
then  on  the  successful  filling  of  the  second  retaining  point. 
Then  his  thoughts  are  upon  the  connecting  of  these  two  fill- 
ings by  a  "first  layer"  of  gold ;  and  all  this  is  at  the  "vulner- 
able spot,"  at  the  disto-cervical  edge.  Not  a  piece  must  move ; 
not  a  piece  "must  miss  its  "  weld ;"  not  a  piece  but  must  be 
placed  with  that  tension  of  accuracy  which  is  so  well  known  to 
those  of  us  who  have  been  repeatedly  prostrated  under  its  de- 
pressing influence,  or  the  work  will  "fail  from  defective  manip- 
ulation." 

It  is  just  here  that  relief  is  sought  by  the  gold-worker  in 
the  possibilities  of  soft  foil  pellets  and  hand  pressure ;  and  it 
is  upon  the  respective  merits  of  soft  gold  and  cohesive,  in  this 
connection,  that  discussion  has  been  going  on  for  thirty  years ; 
the  experiences  of  to-day  are  those  of  a  quarter  of  a  century 
since ;  the  arguments  and  assertions  of  then  are  those  of  now. 
The  subject  has  been  hammered  at  until  it  is  utterly  attenu- 
ated ;  and  in  its  gossamer-like  thinness  it  is  hammered  at  with 
undiminished  vehemence;  so  it  is  evident  that  the  gold- worker 
regards  it  as  worthy  of  much  thought. 

The  records  of  the  last  meeting  of  the  American  Dental 
Association  prove  that  no  conclusion  upon  this  point  has  been 
reached,  so  that  nothing  definite  can  here  be  thought  of  by  the 


Iti  PLASTICS    AND     PLASTIC    FILLING. 

gold-worker ;  but  by  either  mode  the  filling  gradually  grows  ; 
pellet  is  added  to  pellet,  or  fold  after  fold  of  rope  is  inserted, 
or  piece  to  piece  is  united,  until  finally  the  thought  of  the  gold- 
worker  is,  the  gold  is  all  in. 

Next  come  the  thoughts  of  finishing ;  and  this  is  also  a  pro- 
longed task.  Thoughts  of  files  and  burrs  and  stones;  thoughts 
of  corundum  tape,  pumice  and  tutty  powder ;  thoughts  of  bur- 
nishers, flat,  round,  and  ball ;  thoughts  of  the  beautiful,  lus- 
trous soap  polish. 

And  in  this  work,  as  "  hand,  responsive  to  the  thought,"  de- 
velops, step  by  step,  the  "elegant  conception,"  at  last  'tis  fin- 
ished ;  and  some  of  the  final  thoughts  are,  truthfully,  that  "  it 
is  perfectly  magnificent;"  that  "it  is  evidence  of  exceeding 
skill ;"  that  "  it  is  artistic." 

To  all  this  the  worker  in  plastics  says,  Amen  !  But  others 
of  the  final  thoughts  are,  that  "it  is  the  lest  that  could  be 
done ;"  that  "  it  is  a  proof  of  superiority  as  a  dentist ,-"  that 
"  it  is  the  most  durable  as  a  preserver  of  the  tooth." 

To  these  thoughts  the  worker  in  plastics  does  not  say,  Amen  ! 

He  thinks,  "I  would  not  like  to  have  that  kind  of  thing  done 
to  my  tooth."  "It  certainly  does  prove  that  the  gentleman  is  a 
superior  tooth -jeweller  ;  but  I  do  not  yet  exactly  recognize  the 
dental  superiority."  And  he  next  thinks  of  the  teeth  of  that 
kind  which  he  has  seen  in  which  fillings  of  amalgam  and  gutta- 
percha,  SO  COMFORTABLY  INTRODUCED,  have  done  ten  years  of 
service,  and  bid  fair  to  do  years  of  service  yet,  in  which  just 
such  beautifully  polished  jewels  had  failed  in  from  three  to 
eight  years;  and  if  the  gutta-percha  is  worn  and  cupped,  and 
if  the  amalgam  is  discolored,  he  feels  toward  them  as  he  would 
toward  a  stalwart  old  negro  who  had  carried  him  safely  over  a. 
roaring  river, — he  views  leniently  the  scars  and  farrows  wrought 
by  time  and  exposure,  and  even  forgives  the  fellow  for  having 
a  black  skin  ! 

As  with  the  gold-worker,  so  with  the  worker  in  plastics. 
After  the  preparation  of  the  cavity,  next  comes  the  introduction 
of  the  filling ;  but  with  what  different  feelings  and  thoughts 
does  he  come  to  the  work.  Selecting  one  of  his  thinnest  sepa- 
rating-slides  he  bends  it  to  the  desired  shape,  adapting  it  as  a 
broad  clasp  to  the  wisdom-tooth,  with  the  outspoken  thought, 


INTRODUCTORY.  17 

"  it  will  be  less  inflictive  to  withdraw  a  separating-slide  than  to 
cut  a  separation  between  the  filling  and  the  adjoining  tooth 
with  the  cavity  so  deep  under  the  gum  ;"  and  then,  drying  the 
cavity  with  bibulous  paper,  prepares  for  the  introducing  of  his 
material  by  simply  pressing  into  the  cavity  pellets  of  cotton 
moistened  with  oil  of  cloves,  with  just  sufficient  force  to  push 
aside  the  gum  ;  he  next  selects  his  "  submarine  "  alloy,  with 
thoughts  of  the  requirements  and  knowledge  of  its  compo- 
sition and  proportions;  he  recognizes  its  liability  to  discolor, 
but  thinks  of  the  tooth-saving  effect  of  discoloration ;  he  rec- 
ognizes the  difficulties  with  which  he  has  to  contend,  and  thinks 
cheerfully,  both  for  himself  and  the  patient,  of  the  facility  with 
which,  by  his  mode  of  practice,  he  will  overcome  them.  And 
with  these  thoughts  he  has  weighed  and  made  his  material; 
and  now,  removing  the  cotton  pellets  and  again  drying  the 
cavity,  proceeds  dexterously  with  the  insertion  of  the  lower 
stratum  of  his  filling.  With  the  "  rough  trimming "  of  his 
work,  his  thought  is  "  with  what  ease  and  celerity  has  this  so- 
called  difficult  operation  been  transformed  into  one  of  perfect 
simplicity ;"  and  with  the  remark  that  "  it  will  now  have  to 
wait  for  fifteen  or  twenty  minutes,"  he  proceeds  with  another 
preparation  or,  for  the  few  minutes,  dismisses  the  patient.  In 
due  time  he  removes  his  "  slide,"  does  what  little  finishing 
trimming  may  be  required,  and  then  proceeds  to  place  the 
tooth  "under  rubber."  He  has  no  thoughts  of  clamps  or 
clamp-forceps ;  he  has  but  little,  if  any,  thought  of  ligatures ; 
he  has  removed  everything  that  makes  the  placing  of  the  rubber 
a  trying,  difficult,  and  painful  thing  to  the  gold-worker  and  Jris 
patient ;  and  thus,  having  punched  three  or  four  holes,  his  be- 
ginning, instead  of  being  the  forcing  of  a  clamp  far  below  the 
gum, — an  operation  which  must  be/e?£  ONCE  to  be  appreciated, — 
is  the  easy  slipping  of  the  dam  over  the  bicuspids,  and  the  al- 
most equally  easy  successive  damming  of  the  molars;  he  thinks, 
with  much  inward  satisfaction,  that  the  rubber  does  not  have  to 
go  below  the  gum,  and  that,  if  a  ligature  is  needed,  it  can  be 
placed  with  comfort  to  the  patient. 

Then  his  work  may  be  considered  practically  done;  for,  with 
the  cavity  perfectly  dry,  the  manipulation  of  "  plastics  "  is  sure 
and  easy ;   the  low-heat  gutta-percha  adheres  to  the  softened 
2 


18  PLASTICS    AND    PLASTIC    FILLING. 

dentine,  covering  the  pulp  with  a  degree  of  heat  which  is  un- 
noticed even  by  that  sensitive  organism ;  the  quick-setting 
alloy,  of  good  color  test,  is  rapidly  and  effectively  placed  in 
position  without  a  disturbing  thought  of  "flaking,"  "missing 
weld,"  or  "  loosening  of  the  filling  at  the  vulnerable  spot,"  and 
the  final  finishing  on  the  buccal  face  with  the  "  medium  "  gutta- 
percha  completes  a  filling  which  to  the  worker  in  plastics  sug- 
gests a  long  train  of  satisfied  thoughts  as  to  its  acceptable 
introduction ;  its  happy  meeting  of  varied  requirements  ;  its 
presentable,  tooth-like  appearance,  and  its  probable  value  as  a 
durable,  pulp-saving,  tooth-saving,  comfort-giving  operation. 


AKTICLE   I. 
PLASTIC   FILLING. 

T)REMISING  that  the  decided  advantages  which  would  accrue 
J-  from  a  gradually  increasing  employment  of  plastic  filling 
materials  in  connection  with  efforts  for  the  saving  of  teeth,  below 
medium  in  quality,  are  fast  becoming  recognized  by  a  very  large 
portion  of  the  practitioners  of  dentistry,  and  believing  that  their 
successful  utilization  depends  as  much  upon  a  scientific  adapta- 
tion of  means  to  ends,  as  does  the  successful  utilization  of  gold 
depends  upon  manipulative  ability,  I  purpose  offering  some  sug- 
gestions which,  while  they  may  not  fully  educate  to  the  use  of 
"  plastics  "  from  the  high  analytical  standpoint  that  must  entirely 
govern  this  when  based  upon  future  collegiate  instruction,  will, 
nevertheless,  give  such  aid  to  those  who  desire  to  experiment 
in  this  direction  as  will  enable  them  to  produce  results  which 
will  be  eminently  satisfactory  alike  to  patient  and  operator,  and 
this,  too,  in  the  very  cases  where  even  the  most  skilful  manip- 
ulators in  gold  fail  ignobly. 

To  this  end  I  shall  first  discuss  the  indications  which  point 
to  the  employment  of  any  single  plastic  material  for  the  making 
of  a  filling,  and  then  pass  to  the  consideration  of  those  combi- 
nations which  are  the  essentials  to  the  perfect  development  of 
that  system  of  tooth-salvation  which  is  based  upon  the  electro- 
chemical theory  of  Dr.  S.  B.  Palmer,  and  which  attributes  the 
failure  in  operations  mainly  to  "  incompatibility  of  filling  ma- 
terial with  tooth-bone." 

It  is  now  just  twenty-five  years  since.  I  commenced  the 
work  of  "  Systematic  Development  of  Plastic  Filling."  It  has 
been,  with  me,  a  "  labor  of  love,"  one  in  which  I  engaged  under 

19 


20  PLASTICS    AND    PLASTIC    FILLING. 

the  favorable  auspices  of  hearty  encouragement  from  profes- 
sional elders  for  whom  I  had  the  highest  respect :  whose  attain- 
ments as  practitioners  were  unquestioned,  and  whose  allegiance 
to  dentistry  was  undoubted. 

It  lias  been  a  long,  and  sometimes  tedious,  path  which  I  have 
trodden,  but  the  interest  has  been  ever  increasing,  and  the  glean- 
ings from  the  way-side  have  proven  to  me,  and  to  thousands  of 
niv  fellow-creatures,  productive  of  an  ample  harvest  of  mutually 
satisfactory  results. 

During  the  first  six  years,  progress  was  naturally  slow,  but  at 
the  expiration  of  that  period  I  had  obtained  such  data,  as  that 
the  prosecution  of  experiments  seemed  not  only  warrantable, 
but  to  be  demanded. 

As  I  was  early  educated  to  the  value  of  "  a  record  "  I  desired, 
as  a  preliminary  to  long  continued,  further  work,  that  the  con- 
clusions which  had  been  obtained  should  be  recorded,  that  they 
could  be  referred  to,  be  the  outcome  what  it  might. 

To  this  end,  I  proposed,  as  the  subject  for  discussion  at  the 
meeting  of  the  Pennsylvania  Association  of  Dental  Surgeons, 
held  March  12,  1861,  "the  consideration  of  the  so-called  osteo 
plastic  materials  for  filling  teeth.''  Although  the  subject  was 
not  so  stated,  the  discussion  was,  under  direction,  confined  to 
the  then  new  "  oxy-chloride  of  zinc."  As  /  had  "proposed" 
for  that  meeting,  I  asked  my  friend  Dr.  C.  Xewliii  Pierce  to 
propose  "amalgam  "  as  the  subject  for  the  next  meeting,  April, 
telling  him  that  I  desired  particularly  to  obtain  a  general  ex- 
pression of  opinion  in  regard  to  that  material,  and  also  wished 
to  place  myself  upon  record  for  an  especial  purpose. 

Reference  to  the  discussion  of  that  subject  as  found  in  the 
Cosmos  for  May,  1861,  page  548,  will  show  that  I  had  not  only 
the  results  of  my  own  "six  years''  of  observation,  but  the 
markedly  favorable  views  of  the  members  toward  amalgam,  to 
sustain  me  in  a  continued  series  of  investigations  in  connection 
even  with  that  hitherto  questionable  compound. 

This  was,  to  me,  a  matter  for  congratulation,  as  I  was  then 
about  to  commence  a  gradual  increase  in  relative  proportion  of 
plastic  fillings  to  those  of  gold,  and  it  became  important  that 
this  increase  should  be  definite  in  materials  as  well  as  in  degree. 
I  therefore  decided  upon  amalgam,  gutta-percha  stopping,  and 


PLASTIC    FILLING.  21 

oxy-chloride  of  zinc  for  materials,  and  upon  six  per  centum  of 
fillings  as  an  amount  of  annual  substitution  of  plastics  for  gold 
which  would  permit  of  careful  observation  and  of  healthful  prog- 
ress. 

This,  of  course,  could  not  be  done  positively,  but  it  was  done 
so  approximately,  as  that  at  the  close  of  the  ninth  year  I  found 
myself  filling  all  cavities  in  teeth  below  medium  in  structure 
with  plastic  materials. 

By  this  time  the  demands  for  services  had  reached  a  point 
which  permitted  of  selection  of  cases  upon  my  part,  and  I  re- 
solved to  confine  my  work  thenceforth,  as  much  as  possible,  to 
the  saving  of  soft  teeth,  a  labor  which  I  then  recognized  would 
eventuate  in  the  exclusion  of  gold  as  a  filling  material. 

It  can  readily  be  imagined  that  I  viewed  this  result  as  a  matter 
of  serious  import,  for  I  felt  that  its  outgrowth  must  naturally 
be  an  uncompromising  attack  upon  the  time-honored  and  fondly 
cherished  articles  of  belief  that  "  gold  is  the  best  material  for 
filling  teeth,"  and  that  "  eminent  skill  in  working  gold  is  the 
basal  requirement  for  superiority  as  a  dentist;"  but  even  for 
this  I  had  been  collaterally  prepared,  largely  through  the  instru- 
mentality of  my  cherished  friend  and  able  instructor,  Prof. 
Robert  Arthur. 

NOTK.  —  It  is  a  source  of  the  greatest  comfort  to  me  to  have  the  written  proofs 
of  the  warm  friendship  which  existed  between  Prof.  Arthur  and  myself  even  to 
the  period  of  his  last  illness,  and  to  be  able  to  say  that  he  smiled  approvingly 
upon  the  picture  of  himself,  which  he  had  presented  to  me,  when  he  saw  it  in  my 
office  as  the  first  in  the  "Gallery  of  Dental  Heretics." 

I  had  already  enjoyed  the  opportunity  for  observing  the  ex- 
cellent results  of  many  years  of  practice  based  upon  his  teach- 
ing in  regard  to  the  leaving  of  decay  in  cavities,  for  the  protec- 
tion of  the  pulp.  I  had  heard  the  violent  denunciation  with 
which  this  teaching  had  been  assailed,  and  had  seen  the  cold- 
ness with  which  the  "  eminent "  men  of  1860  had  turned  their 
faces  from  this  "  disreputable  "  practice ;  and  I  had  lived  to 
hear  this  innovation  taught,  as  universally  accepted,  and  to  see 
that  the  vast  majority  of  the  virulent  opponents  had  been  forced 
to  practise  upon  this  teaching. 

This  naturally  gave  me  faith  to  believe  that  other  tenets,  if 


22  PLASTICS    AND    PLASTIC    FILLING. 

built  upon  the  sand,  would  fall,  and  that  other  teachings,  if 
founded  on  a  rock,  would  stand. 

Time  and  experiment  would  establish  truth,  and  in  no  other 
way  could  it  be  established ;  therefore,  from  this  period,  I  de- 
clined all  new  patients  with  teeth  above  medium  in  structure, 
and  more  closely  concentrated  my  experiments  upon  such  teeth 
as  are,  even  now,  usually  condemned  to  extraction. 

In  seven  years  more  I  found  myself  with  a  practice  which 
was  and  is,  to  say  the  least,  peculiar. 

It  is  peculiar,  in  that  I  seldom  see  a  denture  which  is  above 
average  in  quality. 

It  is  peculiar,  in  that  I  have  many  hundreds  of  patients  for 
whom  I  have  saved,  for  many  years,  the  remains  of  dentures 
which  had  been  almost  lost  under  excellent  operators  with  gold. 

It  has  been  freely  suggested  to  me  that  it  is  easy  to  save  teeth 
when  all  those  predisposed  to  decay  have  been  extracted !  and 
that  it  is  easier  to  save  teeth  when  arches  are  so  broken  as  to 
permit  a  natural  separation  of  the  teeth  !  and  that  persons'  con- 
stitutions are  apt  to  change,  and  thus  the  teeth  are  less  liable  to 
decay!  but  it  has  seemed  to  me  strange  that  so  many  patients 
have  comeyws^  when  every  tooth  which  ivas  predisposed  to  decay 
had  been  extracted,  and  had  thus  placed  under  my  charge  no 
teeth  except  such  as  were  not  liable  to  decay  !  And  again,  I  have 
wondered  why,  when  arches  were  quite  sufficiently  broken  to 
permit  the  natural  saving  separation  of  the  teeth,  the  loss  should 
be  continued  until  there  were  not  teeth  enough  left  to  permit 
of  natural  mastication !  and  yet  again,  to  me  it  seemed  the  most 
remarkable  of  all,  that  every  patient's  constitution  should 
change  immediately  upon  placing  the  teeth  under  the  influence 
of  plastic  filling  materials  ! 

It  is  peculiar,  from  the  fact  that  I  am  able,  with  such  dentures, 
selected  for  their  frailty,  to  meet  all  indications  without  resort- 
ing to  "  artificial  work."  By  this  term  I  mean  to  refer  to  the 
introduction  of  sets  of  teeth  upon  plates,  either  partial  or  com  • 
plete,  and  do  not  include  as  "  artificial  work  "  the  grafting  of 
porcelain  crowns,  the  insertion  of  plate  teeth  as  faces  to  "  pivot- 
ings  "  or  the  introduction  of  porcelain  as  edges,  corners,  or  as 
"  mosaic  "  fillings ;  all  this  work,  I  think,  is  properly  taught  as 
"  operative,"  and  I  would  be  understood  as  so  regarding  it. 


PLASTIC    FILLING.  23 

During  the  past  eight  years,  the  requirements  of  all  my  patients 
have  not  reached  an  average  of  one  piece  of  artificial  work  per 

annum. 

i 

It  is  peculiar,  in  that  I  have  no  demand  for  gold  as  a  filling 
material.  "When  I  had  reached  this  point,  it  was  with  little  or 
no  surprise  that  I  beheld  this  peculiar  result ;  the  demands  for 
gold  had  been  steadily  diminishing  for  years ;  as  successive 
exigencies  had  arisen,  each  difficulty  had  been  satisfactorily  sur- 
mounted, and  each  surmounting  had  opened  the  way  for  easier 
conquering  of  greater  difficulties ;  in  this  work  the  claims  of 
gold  became  less  obtrusive,  until  they  were  finally  lost  sight  of 
completely. 

With  teeth  which  had  been  filled  and  refilled  with  gold  un- 
til the  expenditure  had  been  enormous ;  until  the  repetition  of 
infliction  had  been  such  that  the  mere  thoughts  of  dental  visits 
had  become  intolerable;  until  the  gradual  increase  in  frequency 
of  extraction  had  become  an  accepted  institution;  until  all  hopes 
of  comfort  or  tooth-salvation  had  been  lost — what  was  there  to 
offer  in  continuance  of  such  practice  ? 

With  those  who  had  honestly  and  earnestly  made  diligent 
inquiry  for  "the  best,"  —  as  best  after  lest  had  failed  to  meet 
their  requirements,  —  and  who  had  availed  themselves  of  ser- 
vices, the  remaining  results  of  which  were  evidences  of  mar- 
vellous skill,  patience,  and  endurance,  and  with  whom  all  had 
proven  but  a  mockery,  what  was  there  to  offer  in  continuance 
of  such  efforts  ? 

With  those  who  were  thoroughly  dissatisfied  with  what  had 
been  done  for  them,  and  who  had  ample  and  unanswerable 
reasons  for  their  views  of  "first-class"  dentistry,  in  what  man- 
ner would  any  proposition  be  received  other  than  for  something 
entirely  different  in  dental  work  from  anything  which  they  had 
previously  experienced  ? 

Under  such  circumstances,  what  more  positively  unavoidable 
than  the  "abandonment  of  gold"?  And  now,  as  the  result 
of  an  immense  experience  reaching  through  a  period  of  over 
twenty  years,  I  have  arrived  at  the  same  conclusion  with  my 
friend  Prof.  H.  S.  Chase,  and  most  emphatically  endorse  his 
enunciation,  "  In  proportion  as  teeth  NEED  SAVING,  gold  is  the 
worst  material  to  use." 


24  PLASTICS    AND    PLASTIC    FILLING. 

AETICLE  II. 
AMALGAM. 

"  About  the  year  1826,  M.  Taveau,  of  Paris,  advocated  the  use  of  what  he 
called  '  Silver  paste,'  for  permanent  fillings.  Under  this,  as  it  were,  shining  title, 
was  ushered  into  the  world  what  was  destined  to  be  for  years  the  Hydra  of  den- 
tistry."—  History  of  Dental  and  Oral  Science  in  America,  page  61. 

THIS  metallic  preparation  for  filling  cavities  of  decay  in  teeth 
was  first  brought  to  the  notice  of  the  dental  profession  in 
the  United  States,  about  fifty  years  ago,  through  the  advertise- 
ments of  two  Frenchmen  by  the  name  of  Crawcour. 

It  was  called  by  them  the  "  Royal  Mineral  Succedaneum," — 
succedaneum,  a  replacer  or  substitute,  —  a  name  which  is  in- 
dicative of  fraud,  and  which,  consequently,  stamps  the  adven- 
turers as  unworthy  of  professional  respect. 

Had  these  persons  been  unsuccessful  pecuniarily,  it  is  more 
than  possible  no  notice  would  have  been  taken  either  of  them 
or  their  filling  material ;  but,  as  it  was  otherwise,  and  as  they 
induced  a  really  large  number  of  the  "  best  people "  to  submit 
to  their  operations,  a  shower  of  indignant  epithets  was  heaped 
upon  them  by  the  incensed  "  first-class  "  practitioners  of  that 
day. 

From  the  fact  that,  among  other  desirable  qualities,  the  then 
new  filling  material  was  "  easily  manipulated,"  its  possessors 
were  enabled  to  fill  a  class  of  largely  decayed  teeth,  with  frail 
and  broken  cavity  walls,  such  as  had  never  been  attempted  by 
the  most  skilful  operators  then  in  practice. 

This  naturally  reflected  to  their  discredit  and  to  the  en- 
hancing of  the  reputation  of  the  Crawcours.  It  was  in  vain  that 
asseverations  as  to  the  impropriety  of  retaining  such  "worth- 
less'' teeth  in  the  mouth  were  made  by  those  highest  in  au- 
thority. The  comfort  and  satisfaction  evinced  by  such  as  were 
enjoying  the  tangible  benefits  of  the  "new  discovery"  far  more 
than  counterbalanced  the  impression  made  by  the  scientific 
theorists. 

This  state  of  affairs,  however,  was  not  of  long  duration. 
Every  occasional  swelling  of  a  face  —  attributable,  as  we  now 


A  M  A  L  G  A  M  .  25 

know,  to  existing  conditions  prior  to  filling,  and  which  an 
equally  tight  stopping  of  any  other  material  would  have 
equally  induced,  —  was  accredited  to  the  "  Succedaneum,"  and 
from  this  false  basis  every  sufferer  was  enlisted  as  an  antago- 
nist to  the  "  Eoyal"  filling  material. 

It  was  soon  proven  that,  instead  of  the  material  being  a  min- 
eral compound,  it  was  purely  metallic,  and  consisted  of  silver 
and  copper  rendered  temporarily  plastic  by  the  addition  of 
mercury. 

This  knowledge  was  eagerly  spread  abroad  among  the  peo- 
ple;  and  every  case  of  excessive  flow  of  saliva  —  now  recog- 
nized as  a  very  frequent  concomitant  of  periodontitis,  and  par- 
ticularly of  alveolar  abscess — was  pronounced  mercurial  ptyal- 
ism;  and  direful  tales  of  wholesale  loss  of  teeth  and  large  por- 
tions of  jaw-bone  were  freely  circulated. 

And  yet,  despite  all  this,  the  use  of  amalgam  steadily  in- 
creased. As  years  rolled  by,  the  number  of  those  practising 
dentistry,  who  employed  it,  was  becoming  seriously  great. 
Gentlemen  who  had  some  claim  to  proficiency  as  manipulators 
and  respectability  as  practitioners  were  admitting  that  its  use 
was  warrantable  in  some  cases.  Doubts  were  beginning  to  be 
expressed  as  to  the  truth  of  the  objections  which  had  been 
urged  against  it ;  and  still  more  decided  opinions  were  held  as 
opposed  to  the  effects  —  either  local  or  systemic  —  which  had 
been  attributed  to  it. 

Under  these  circumstances,  it  was  deemed  needful,  for  the 
proper  maintenance  of  the  dignitj^  and  purity  of  the  Profes- 
sion, that,  as  there  had  been  organized  an  American  Society 
of  Dental  Surgeons,  such  official  action  should  be  taken  by 
that  body  as  would  place,  beyond  discussion,  the  line  of  demar- 
cation between  scientific  regularity  and  discreditable  irregu- 
larity. 

As  the  initiative  in  this,  a  committee  was  appointed  in  the 
year  1841  for  the  purpose  of  reporting  upon  all  filling  materials 
of  which  mercury  was  a  component. 

This  committee  reported  that  the  use  of  all  such  materials 
was  injurious  both  to  teeth  and  mouths,  and  that  there  was  no 
tooth  which  could  be  serviceably  filled  that  could  not  be  filled 
with  gold. 


26  PLASTICS    AND     PLASTIC    FILLING. 

The  report  of  the  committee  was  adopted  by  the  society 
unanimously. 

But  even  this  could  not  stay  the  onward  course  of  the  ob- 
noxious compound ;  for,  in  the  year  1843,  it  was  found  neces 
sary  to  pronounce  the  use  of  amalgam  "malpractice." 

This  declaration  seems  to  have  been  the  culmination  of  the 
solid  wave  of  opposition ;  for,  at  this  time,  "  information  and 
facts "  having  been  gathered  and  laid  before  the  Medical 
Society  of  the  County  of  Onondaga,  New  York,  it  was  re- 
ported as  their  opinion  that,  although  the  "mineral  paste"  had 
undoubtedly  produced  mercurial  (?)  effects  both  severe  and  alarm- 
ing, yet,  nevertheless,  the  proportion  of  such  cases  was  small 
when  compared  with  the  great  number  of  instances  in  which 
it  had  been  employed ;  "  but  that  no  care  in  the  combination 
or  use  of  the  paste  will  prevent  its  occasional  bad  effects." 

This  was  not  the  kind  of  report,  by  any  means,  that  the 
opponents  of  amalgam  desired,  as  it  was  calculated  to  weaken, 
rather  than  to  strengthen,  their  cause,  and  did  eventuate  in 
more  critical  investigation  of  the  subject  at  the  hands  of 
gentlemen  who  were  not  blinded  by  prejudice,  but,  on  the 
contrary,  were  actuated  by  a  desire  to  judge  intelligently  in 
regard  to  the  matter. 

Then  it  was  that  fillings  of  the  decried  material  having  done 
ten  years  of  acceptable  service  in  teeth  that  had  been  con- 
demned by  eminent  practitioners  as  unworthy  the  effort  to  save, 
were  brought  under  the  observation  of  those  who  recognized 
evidences  of  its  value  in  these  enduring  and  continuing  proofs 
of  its  capability. 

Gradually  some  of  the  "  better  men  "  began  to  advocate  its 
occasional  employment,  and  so  openly  was  this  done,  that  the 
leaders  of  that  day  — 1845  —  felt  that  the  time  for  the  most 
energetic  action  had  arrived,  and,  actuated,  as  we  believe,  by 
a  conscientious  conviction  as  to  the  imminent  danger  which 
threatened  the  profession,  and  through  it  those  who  relied 
upon  its  members  for  the  saving  of  their  teeth,  "Resolved, 
That  a  committee  of  investigation  be  appointed." 

The  duty  of  this  committee  was  that  of  calling  upon  each 
and  every  member  of  the  aforesaid  American  Society  of  Den- 
tal Surgeons  and  ascertaining  his  views  in  approval  or  disap- 


AMALGAM.  27 

proval  of  amalgam,  and  as  to  whether  he  used  it  in  his  prac- 
tice. 

Although  this  resolution  was  adopted,  it  was  not  until  it  had 
been  most  warmly  discussed ;  and  it  is  worthy  of  note,  as  illus- 
trating the  gradual  changing  of  opinions,  that  Dr.  E.  Baker  and 
Dr.  Solyman  Brown,  both  of  whom  were  members  of  the  com- 
mittee of  1841,  whose  report  has  been  referred  to,  spoke  against 
the  resolution. 

The  report  of  this  committee  was  to  the  effect,  that  of  nearly 
fifty  members  visited,  less  than  a  dozen  ever  used  amalgam,  and 
only  three  positively  refused  to  pledge  themselves  not  to  do  so. 
It  further  insisted  that  any  amalgam  was  dangerous  and  unfit  for 
use  as  a  filling  material,  and  concluded  with  this  memorable  sen- 
tence : 

"  That  any  member  of  this  society  who  shall  hereafter  refuse  to 
sign  a  certificate  pledging  himself  not  to  use  any  amalgam,  and, 
moreover,  protesting  against  its  use,  under  any  circumstances,  in 
dental  practice,  shall  be  expelled  from  this  society" 

That  any  such  action  should  have  disgraced  the  records  of 
any  scientific  body  in  this  country,  during  this  nineteenth  cen- 
tury, is  well-nigh  incredible ;  but  that  it  should  have  occurred 
within  the  ranks  of  dentistry,  and  that,  too,  while  it  was  in  the 
first  throes  of  young  life  as  a  distinct  profession,  when  liber- 
ality, brotherly  love,  and,  above  all,  the  most  perfect  freedom 
of  scientific  thought  and  investigation  should  have  been  ten- 
derly nurtured,  is  simply  monstrous. 

It  is  comforting  that  we  are  able  to  relate  the  burst  of  con- 
demnation which  greeted  this  resolution  of  expulsion ;  hun- 
dreds of  practitioners,  society  men,  and  others,  while  declaring 
themselves  opposed  to  the  use  of  amalgam,  also  declared  them- 
selves as  much  more  opposed  to  the  wretched  policy  which 
threatened  punishment  as  the  reward  for  investigation  and  ex- 
perimentation. 

At  the  next  meeting  of  the  society  in  1847,  for  using  amal- 
gam and  refusing  to  sign  the  required  pledge,  eleven  members 
were  expelled. 

The  society  had  now  done  its  "  worst,"  and  in  so  doing,  it  did 
its  best!  Instead  of  interfering  with  the  use  of  amalgam,  even 
in  the  least  degree,  its  action  stimulated  more  practitioners  to  a 


28  PLASTICS    AND     PLASTIC    FILLING. 

critical  investigation  of  the  merits  and  demerits  of  a  material 
which  had  so  exercised  the  minds  of  the  leading  men  as  to  have 
shaken  dentistry  to  its  centre. 

The  earnest  workers  wrought  on  till  1850 ;  each  year  added 
to  the  proofs  of  the  value  of  the  condemned  material;  wretch- 
edly compounded ;  wretchedly  manipulated;  wretchedly  abused ; 
it  was  yet  standing,  after  a  trial  of  nearly  twenty  years,  in 
many  a  tooth  which  had  been  filled  by  the  pretentious  French- 
men !  More  carefully  compounded  ;  with  better  manipulation ; 
and  judiciously  used  instead  of  badly  abused,  it  had  given  such 
convincing  evidence  of  its  utility,  and  had  even  so  long  ago 
lived  down  so  much  of  false  aspersion,  as  that  many  of  the 
members  of  the  American  Society  felt  it  a  duty  that  the  action 
of  1845  should  be  revoked,  and  the  error  of  judgment  evinced  in 
the  proceeding  be  fairly  acknowledged. 

This  feeling  gave  rise  to  more  discussion,  which  resulted  in 
the  appointment  of  a  committee  to  take  into  consideration  the 
propriety  of  rescinding  the  former  resolutions  of  "  pledge  "  and 
"  expulsion." 

If  the  former  action  of  the  society  was  characterized  by 
narrow-minded  bigotry,  the  report  of  this  committee  was  even 
worse.  It  is  true,  that  it  recommended  that  the  resolutions 
which  enforced  the  "  subscription  to  the  protest  and  pledge 
against  the  use  of  amalgam  and  mineral  paste  fillings  for  teeth, 
be,  and  the  same  are,  hereby  rescinded  and  repealed ; "  but  it 
did  so  avowedly  "  upon  the  belief  that  the  resolutions  had  accom- 
plished the  object  for  which  they  were  designed,  and  there  no 
longer  existed  any  necessity  for  their  enforcement."  Can  this  be 
credited?  And  yet  this  is  the  record  of  the  transaction. 

Again  we  are  comforted  in  the  knowledge  that  this  con- 
temptible method  of  treating  so  important  a  matter  resulted 
in  the  immediate  resignation  of  quite  a  number  of  the  members. 

Again  the  years  rolled  on;  as  truth  was  mighty  and  pre- 
vailed, so  the  society  dwindled  year  by  year,  until  at  last,  having 
lost  all  its  former  prestige,  a  meeting  was  held  at  which  the 
President — Dr.  Elisha  Townsend — was  directed  to  call  a  meet- 
ing for  the  consideration  of  "  dissolution."  At  the  meeting  of 
1855,  a  committee  upon  this  subject  was  appointed.  This  com- 
mittee reported  against  dissolution,  was  continued,  and  the 


AMALGAM.  29 

meeting  adjourned  to  meet  in  New  York  on  the  first  Tuesday 
of  August,  1856.  At  that  meeting  —  a  very  small  one  —  the 
following  committee  report  was  adopted  : 

"  That  we  deem  it  expedient  to  dissolve  this  association,  and- 
that  it  be  and  is  hereby  adjourned  sine  die" 


AETICLE   III. 
AMAL  GAM.— Continued. 

IT  seems  to  me,  that,  for  the  future  good  of  dentistry,  two 
facts  are,  at  this  time,  worthy  of  careful,  thoughtful  consid- 
eration:— 1st.  That  amalgam,  which,  from  its  misuse  and  abuse 
at  the  hands  of  those  who  attempted  to  utilize  it,  had  become  an 
object  of  unmitigated  contempt  to  those  who  were  recognized 
as  representative  men,  has  practically  proven  itself  to  possess 
qualities  such  as  have  compelled  respectful  recognition  as  a 
most  valuable  filling  material ;  and, 

2d.  That  such  radical  change  of  opinion  in  regard  to  amal- 
gam had  been  wrought,  by  some  means,  during  the  passing  of 
twenty  years,  as  that  the  official  acts  which  were  esteemed  need- 
ful in  opposition  to  its  use,  so  far  from  accomplishing  their  pur- 
pose, were  directly  instrumental  in  the  final  dissolution  of  the 
attacking  organization. 

These  two  points  alone  should  furnish  sufficient  reason,  to  all 
who  have  professional  interest  in  this  matter,  for  the  exercise 
of  every  effort  at  obtaining  information  in  relation  to  it,  and  for 
the  closest  scrutiny  of  all  statements,  either  favorable  or  unfa- 
vorable, regarding  this  very  peculiar  combination  of  metals. 

But  it  is  not  alone  the  two  facts  of  gradually  growing  recog- 
nition on  the  one  hand,  and  final  "dissolution"  of  organized 
antagonism  on  the  other,  that  the  career  of  amalgam  presents 
for  our  reflection,  but  the  equally  significant  ones  that  some  of 
its  strongest  opponents  were  early  found  arrayed  upon  the  side 
of  its  advocates,  and  were  giving  proof  of  the  earnestness  of 
their  convictions  by  its  frequent  use  in  practice.  Some  of  the 
men  whose  names  are  found  upon  the  first  records  of  the 
"amalgam  war"  as  loudly  outspoken  in  condemnation  of  the 


30  PLASTICS    AND    PLASTIC    FILLING. 

material,  are  those  who  in  the  later  of  the  "  twenty  years  "  are 
but  little  less  moderate  in  their  views  of  its  "unquestionable 
value  in  certain  cases." 

1  But,  as  though  all  this  was  not  sufficient  for  amalgam — as 
though  to  show  completely,  and  beyond  all  cavil,  its  inherent 
power  for  overcoming  opposition — we  find,  "  strangest  of  all," 
that  in  the  very  year — 1855 — when  "  dissolution  "  of  the  oppo- 
sing organization  was  proposed,  and  when  it  was  found  that 
the  American  Society  of  Dental  Surgeons  actually  did  not  pos- 
sess sufficient  strength  to  die  (?),  its  President,  Prof.  Elisha 
Townsend,  one  of  the  best  gold-workers  of  his  day,  gave  den- 
tistry his  sanction  to  the  first  formula  for  the  making  of  an 
alloy  for  amalgam  that  ever  had  the  least  pretension  to  "  re- 
spectability" 

This  he  did  as  the  result  of  deliberate  conclusions ;  as  the 
result  of  long-continued,  careful  observations ;  as  the  result  of 
an  earnest  desire  to  aid  more  than  he  had  ever  done — and  that 
was  very  largely — in  the  preservation  of  teeth. 

This  he  did  because  he  saw,  "  daily,  the  evidence  that  teeth 
could  be  saved  with  amalgam  which  he  could  not  save  with 
gold." 

As  one  of  the  most  competent,  the  most  enthusiastic,  and 
the  most  conscientious  practitioners  of  his  profession,  he  pos- 
sessed a  breadth  of  base  which  permitted,  nay,  insisted  upon,  a 
mental  recognition  of  merit  wherever  evidence  of  its  existence 
could  be  shown. 

As  an  ardent  lover  of  his  calling,  he  welcomed  any  aid  in 
the  development  of  its  resources  in  the  struggle  for  relief  to 
suffering,  and  grandly  proved  his  noble  disregard  of  "  self"  by 
accepting  that  which  he  felt  to  be,  at  least  in  some  degree, 
worthy,  even  though  it  came  in  the  "  questionable  shape  "  of 
old-fashioned,  coin  amalyam. 

He  recognized  its  merits,  ease  of  manipulation,  capability 
for  accurate  adaptation  to  cavity  walls,  sufficiently  resisting 
to  subserve  the  purposes  of  mastication,  and  proven  eminently 
tooth-preserving. 

He  recognized  its  demerit  —  its  one  demerit  —  discoloration: 
it  turned  black ;  it  discolored  the  teeth ;  it  disfigured  the 
mouth. 


AMALGAM.  31 

The  cry  of  "  mercurial  ptyalism  "  he  had  not  found  to  be  sus- 
tained by  his  observations.  He  felt  that  the  material  had  been 
unjustly  dealt  with,  unjustly  maligned,  unjustly  condemned  ; 
and  regarding  it  as  one  of  the  "  defiant  down-trodden,"  he  re- 
solved to  give  it  aid  and  countenance  for  its  merits,  and  to  work, 
if  possible,  in  the  direction  of  its  improvement. 

In  young  life  he  had  been  taught  the  trade  of  the  jeweller, 
and  with  the  ideas  thus  inculcated,  he  naturally  accepted,  as  an 
improvement,  the  "refining"  of  the  metals. 

It  was  thought  that  by  the  purifying  of  the  silver,  the  elim- 
ination of  the  copper,  —  which  was  then  held  to  be  a  very 
objectionable  ingredient, —  and  the  addition  of  a  large  propor- 
tion of  pure  tin,  an  alloy  could  be  produced  which  would  be 
decidedly  less  objectionable  than  the  silver  coin. 

The  proportions  of  this  alloy  —  afterward  known  as  Town- 
send's  —  were 

Pure  Silver 4  parts. 

Pure  Tin 5  parts. 

The  metals  were  thoroughly  mixed  while  molten,  and  were 
then  cast  into  matrices  so  shaped  as  to  form  ingots  suited 
either  for  filing  with  a  coarse  file,  or  for  turning  into  shavings 
in  a  lathe :  these  shavings  were  then  rubbed  into  a  sort  of 
powder. 

To  the  required  quantity  of  alloy,  thus  prepared,  was  added 
a  portion  of  mercury,  and  these  were  mixed  in  the  palm  of  the 
hand  by  kneading  with  a  finger.  By  this  means  a  metallic 
mixture  of  doughy  consistence  was  obtained,  wThich  might  very 
appropriately  be  called  a  "  silver  paste." 

This  was  then  further  "  purified  "  by  a  process  known  as 
"  Washing."  For  this,  the  amalgam  mass  was  placed  in  a  small 
porcelain  mortar  and  rubbed  with  a  pestle,  after  having  had 
added  to  it  a  little  absolute  alcohol ;  the  result  of  this  rubbing- 
was  a  decided  blackening  of  the  alcohol,  which  was  then  poured 
off,  and,  with  the  addition  of  more  alcohol,  the  work  of  rubbing 
was  repeated  ;  after  two  or  three  such  "  washings  "  —  as  they 
were  styled  —  much  less  "blackening"  was  produced,  and  it 
was  therefore  assumed  that  this  process  would  prevent,  or  at 
least  diminish,  discoloration.  The  mass  was  then  placed  in 


32  PLASTICS    AND    PLASTIC    FILLING. 

chamois  skin,  and  the  surplus  mercury  having  been  "  squeezed" 
out  by  pliers,  it  was  packed,  artistically,  into  cavities  of  decav. 

As  we  look  at  all  this,  with  the  aid  of  such  light  as  has  been 
thrown  upon  the  subject  by  years  of  systematic,  scientific, 
metallurgic  experimentation,  it  seems  very  like  many  other 
lines  of  work  prosecuted  with  the  very  best  intentions,  but 
based  entirely  upon  the  crudest  and  most  fallacious  assumptions. 

Not  one  of  the  various  proposed  "  purifying  "  processes  was 
possessed  of  any  value ;  and,  what  is  indeed  most  peculiar,  not 
one  is  other  than  detrimental! 

A  filling  material  was  made  which  is  not  nearly  so  tooth  pre- 
serving, and  which,  though  it  is  prevented  from  discoloring  — 
in  limited  degree  —  by  the  addition  of  tin,  is,  by  this  modifi- 
cation, caused  to  "  shrink "  most  notably,  and  from  which  is 
taken,  practically,  all  its  "edge- strength."  The  "washing" 
process,  so  far  from  being  advantageous,  is  proven  to  be  other- 
wise, and,  at  the  present  day,  nearly  all  manufacturers  of  alloy 
for  amalgam  caution  against  it  in  italics  or  capital  letters ! 

And  yet,  the  dental  profession,  in  the  persons  of  its  repre- 
sentative men,  welcomed  with  open  arms  the  tinned  and 
"washed"  amalgam,  as  introduced  by  the  President  of  its 
American  Society  of  Dental  Surgeons,  and  fairly  revelled  in 
the  seemingly  inexhaustible  capabilities  of  this  "  purified " 
sinner ! 

The  largest  and  most  inaccessible  cavities  in  the  frailest  and 
"most  worthless"  of  teeth  were  filled  just  as  the  Crawcours 
had  filled  them!  Crowns  were  built  upon  the  roots  of  molars 
and  bicuspids,  and  were  viewed  with  complacent  pride,  with  no 
thought  of  disgrace,  with  no  fear  of  mercurial  ptyalism ! 

Some  enthusiasts  even  went  so  far  as  to  make  rows  of  crowns 
upon  cuspid  and  incisor  roots,  and  then  stepped  back  to  admire. 

This  was  a  change,  indeed.  It  is  true,  there  were  some  who 
never  joined  in  this  acceptance ;  but  it  is  also  noteworthy  that 
the  later  record  of  such  has  not  placed  them  in  any  position 
which  entitles  them  to  rank  as  equal  in  professional  attainments 
with  most  of  those  who  warmly  espoused  amalgam. 

This  state  of  things  continued  but  for  a  few  years,  —  some 
three  or  four,  — for,  in  this  length  of  time,  not  only  had  "  un- 
worthy" men,  in  numbers,  abused  the  trust  offered  under  the 


AMALGAM.  33 

mantle  of  respectability,  but  much  crevicing  between  fillings 
and  teeth  had  taken  place  from  undue  shrinkage,  and  much 
breaking  away  of  edges,  both  of  fillings  and  cavity  walls,  was 
only  too  apparent;  but,  worst  of  all,  the  "  purification"  by  fire 
and  by  alcohol  had  not  proven  equal  to  the  emergency ;  and 
though  the  discoloration  of  fillings  and  of  teeth  was  not  nearly 
so  great  as  with  the  coin  amalgam,  yet  it  was,  nevertheless,  far 
too  much  for  the  properly  aesthetic  ideas  of  good  gold- workers, 
and  thus  the  tide  began  to  turn. 

Again,  it  was  now  time  for  much  of  the  pathological  se- 
quellre  which  naturally  pertains  to  teeth  that,  having  been 
largely  decayed  and  filled,  permit  a  more  or  less  gradual,  and 
more  or  less  painless  devitalization  and  disintegration  of  their 
pulps.  And  thus  it  was  that  with  quite  an  amount  of  disap- 
pointment in  regard  to  the  frequent  occurrence  of  plug-discol- 
oration, and  with  increasingly  unsatisfactory  statistics  in  con- 
nection with  subsequent  peridental  irritation  and  alveolar 
abscess,  the  dental  mind  became  exercised  in  such  degree  that 
some  of  those  who  were  then  recognized  as  leading  men  ob- 
tained from  Prof.  Townsend  the  following  "  recantation,"  as  it 
was  called,  which  was  published  in  the  "  Dental  News  Letter  " 
of  April,  1858. 

"  For  the  Dental  New*  Letter. 

"AMALGAM. 

"  MESSRS.  EDITORS. — I  promised  to  report  to  you  any  change  in  my 
practice  in  the  use  of  amalgam  for  filling  teeth,  founded  upon  further 
experience.  In  all  that  I  have  ever  said  or  written  upon  amalgam,  I 
have  been  very  careful  not  to  advocate  its  use  except  in  those  cases 
which  could  not  be  filled  with  gold,  and  where  extraction  was  the  only 
alternative.  I  find  my  name  has  been  used  as  authority  for  its  indis- 
criminate and  unlimited  use,  which  I  certainly  never  intended  or  sup- 
posed could  happen. 

"  I  wish  now  to  say  to  the  profession  that  I  have  entirely  abandoned 
it,  and  shall  never  use  it  again  in  my  practice.  I  have  come  to  this 
resolution  for  reasons  which  I  will  now  state.  In  many  of  the  cases 
where  I  most  relied  upon  it,  and  expected  to  have  the  best  results,  it 
has  entirely  failed;  as  in  the  buccal  cavities  in  molars,  when  they  ex- 
tended beneath  the  free  margin  of  the  gum,  I  found  that  while  in  some 
mouths  the  material  remained  white  and  clean,  in  others  it  became 
very  black  in  a  few  days,  and  in  almost  all  cases,  upon  removing  the 
filling,  the  under  side  was  blackened,  and  the  same  color  given  to  the 
3 


34  PLASTICS    AND    PLASTIC    FILLING. 

tooth.  Again,  in  the  infirm  teeth,  for  which  it  seemed  the  only  thing, 
and  for  which  it  was  best  adapted  by  its  plastic  nature,  many  of  them 
had  to  be  removed,  owing  to  suppuration  of  the  gums,  caused  by  the 
tight  closing  of  the  previous  vent  for  the  escape  of  pus. 

"Therefore  I  have  come  to  this  broad  conclusion,  that  a  tooth  so  in- 
firm as  to  need  a  soft  filling  would  be  best  removed,  for  the  health  of 
the  mouth  and  the  health  of  the  patient;  and  that  my  practice  hereaf- 
ter will  be  to  advise  their  removal,  and  then  leave  the  responsibility 
with  the  patient.  ELISHA  TOWNSEND. 

"  No.  1606  Locust  Street." 

As  it  was  entirely  owing  to  Prof.  Townsend's  faith,  in  the 
tooth-saving  quality  of  amalgam  that  I  had  been  induced  to 
commence  experimenting  with  it,  and  as  I  had  gradually  come 
to  regard  even  the  discoloration  of  coin  amalgam  as  a  matter 
of  comparatively  little  moment  in  non-conspicuous  places,  when 
contrasted  with  the  comfortable  and,  as  it  seemed,  durable 
saving  of  a  large  class  of  truly  valuable  teeth,  it  was  with  pe- 
culiarly painful  professional  feelings  that  I  viewed  this  retro- 
grade step — as  I  thought  it — in  that  work  which  I  esteemed 
a  progressive  movement. 

As  it  was,  the  latter  part  of  the  "recantation"  took  from  it 
all  its  power  for  controlling  me. 

I  had  just  then  finished  a  line  of  work  upon  the  systematic 
treatment  of  such  teeth  as  were  specifically  classed  as  appropri- 
ate for  amalgam,  with  the  view  to  preventing  the  occurrence 
of  such  untoward  results,  and  was  then  instructing  my  private 
pupils  in  such  pathology  and  therapeutics  of  alveolar  abscess 
as  I  have  since  taught  and  demonstrated  in  my  lectures  and 
clinics. 

I  had  also  entered  upon  that  protracted  individual  labor 
which  culminated  at  the  meeting  of  the  American  Dental 
Association  of  1875,  when  I  joined  my  friend,  Dr.  S.  B.  PALMER, 
with  the  conviction  that  his  theory  regarding  the  need  for 
"compatibility"  between  filling-material  and  tooth-bone,  as  an 
essential  for  success  in  saving  teeth,  satisfactorily  explained  the 
results  which  my  accumulated  statistics  of  twenty  years  had 
placed  before  me. 

I  engaged  in  that  work  with  the  full  recognition  of  three 
basal  positions  in  connection  with  amalgam  : 

First.     That  one  of  the  very  best  operators  of  his  time  — 


AMALGAM.  35 

Prof.  Townsend  —  had  conceded  that  amalgam  was  a  material 
possessing,  from  some  cause,  a  power  for  saving  teeth  which 
exceeded  that  of  gold,  even  when  worked  with -his  remarkable 
manipulative  skill. 

Second.  That  all  previous  opposition  to,  and  aspersion  of, 
amalgam  had  been  founded  upon  complete  ignorance  of  it ;  while 
the  evil  results  which  were  ascribed  to  it  were  certainly  attrib- 
utable to  other  well-recognized  causes ;  and, 

Third.  That  the  efforts  at  correcting  its  demerit,  though 
well-meant,  were  misdirected. 

It  is  at  this  point  that  I  wish  it  to  be  distinctly  understood 
and  remembered,  that  the  positively  deteriorating  effects  of  the 
change  of  formula  from  silver,  copper,  and  mercury,  to  tin, 
silver,  and  mercury,  as  accepted  and  advocated  by  Prof.  To\vn- 
send,  were  not  recognized  for  many  years.  It  was  not  suspected 
.that  the  "  shrinkage  "  of  the  so-called  Townsend's  amalgam  ex- 
ceeded enormously  that  of  the  silver  coin  amalgam ;  indeed,  it 
was  believed  and  taught  by  Prof.  Townsend  that  amalgam  ex- 
panded during  its  crystallizing,  hardening  just  as  does  water 
while  passing  from  the  fluid  to  the  solid  condition  in  freezing. 

It  was  not  recognized  that  the  sustaining  "  edge-strength  '* 
of  the  old  amalgam  was  seriously  impaired  by  the  lavish  in- 
corporation of  tin.  It  was  not  known  that  the  increv 
"bulging,"  due  to  the  less  controlled  mercurial  tendency  to  as- 
sume spheroidal  shape,  was  the  cause  of  "  crevicing,"  such  as 
was  never  seen  in  connection  with  the  old  material. 

It  was  not  known  that  the  "  setting  "  of  the  new  amalgam 
was  even  slower  than  that  of  the  old ;  for  few,  indeed,  of  these 
"respectable  "  experimenters  knew  anything  of  the  setting  of 
any  other  compound. 

It  was  alone  recognized  that  the  discoloration,  though  modi- 
fied, was  not  sufficiently  so  to  meet  with  anything  but  general 
disapproval.  This  was  the  situation  when  I  commenced  amal- 
gam work  in  1855. 

The  first  positions  to  establish  were  those  of  the  truth  of  the 
assumption  that  amalgam  possessed  a  "tooth-saving  power" 
which  did  not  pertain  to  gold ;  that  instead  of  being  "dangerous 
and  unfit  for  use,"  it  was  advantageous,  and,  under  certain  cir- 
cumstances, eminently  fit  for  use ;  and  that  instead  of  being 


36  PLASTICS    AND    PLASTIC    FILLING. 

"  malpractice "  at  all  times  to  employ  it,  it  was  decidedly 
"  malpractice,"  at  times,  not  to  bestow  upon  patients  the  great 
good  of  its  utilization. 

This  could  only  be  done  by  first  learning  its  proper  mode  of 
manipulation ;  then  filling  a  large  number  of  cavities  in  teeth, 
where  its  behavior  could  .be  compared  with  that  of  gold,  and 
afterward  waiting  for  a  sufficient  number  of  years  in  order  to 
determine  this.  Accordingly,  I  resolved  to  fill  some  hundreds 
of  cavities  with  amalgam  in  teeth  such  as  were  usually  ex- 
tracted, or  were  only  filled  either  by  protracted  operations  with 
tin-foil,  or  by  equally  tedious  and  vastly  more  expensive  oper- 
ations with  gold. 

As  this  work  progressed, — done,  as  it  naturally  would  be, 
with  the  only  amalgam  with  which  I  was  practically  conver- 
sant, "  Townsend's," — the  possibilities  of  the  material  presented 
themselves  with  increasing  clearness ;  and  thus  it  was  that,  led 
on  step  by  step,  I  gradually  treated  and  filled  comfortably  a  class 
of  teeth  which,  even  to  my  developing  conceptions,  was  some- 
thing extraordinary,  until,  within  two  years,  it  seemed  to  have 
become  the  task  to  question,  not  the  necessity  for  extraction, 
but  the  limit  to  possibility  for  salvation. 

I  had  decided  upon  Jive  years  as  a  reasonable  length  <>f 
time  for  the  determination  of  the  question  of  "superiority 
as  a  tooth-saving  material,"  and  so  markedly  had  this  been 
shown  at  the  expiration  of  that  period,  that  I  should  certainly 
have  questioned  my  own  ability  with  gold  were  it  not  that  /'// 
many  mouths  I  had  also  had  the  opportunity  of  contrasting 
with  amalgam  work  many  fillings  of  gold,  of  comparatively 
recent  introduction,  which  were  the  work  of  those  who  were 
deservedly  ranked  as  "  first-class  "  operators. 

At  the  close  of  the  five  years  of  probation,  the  time  did  not 
seem  so  long  to  look  back  upon  as  it  had  seemed  to  look  for- 
ward to,  and  so  I  gave  another  year. 

At  the  end  of  this  time,  I,  too,  became  convinced  that  / 
could  "save  teeth  with  amalgam  which  /  could  not  save  with 
gold,"  and  that  therefore  it  was  my  duty  to  myself,  and  to  those 
who  were  committed  to  my  charge,  to  use  the  means,  the  value 
of  which  I  had  so  thoroughly  tested. 


AMALGAM.  37 

ARTICLE   IV. 
AMALGAM. — Continued. 

FEOM  1861  to  1875,  a  period  of  fourteen  years,  my  progress 
in  the  substitution  of  amalgam  for  gold  had  been  very 
considerable,  and  had  been  attended  with  very  satisfactory  re- 
sults ;  this,  however,  had  been  largely  due  to  the  "  combina- 
tion" fillings  —  oxy-chloride  of  zinc,  sub-strata,  and  linings, 
which  I  had  used  since  1860 ;  but  it  was  also  due,  in  part, 
to  my  gradual  change  of  formula  from  that  of  the  so-called 
"  Townsend's." 

This  formula,  "  Townsend's,"  had  also  gradually  changed ;  but 
while  it  had  done  so  by  greater  addition  of  tin,  and  had  become 
6  parts  of  tin  to  4  of  silver,  the  alloy  to  which  I  had  been  led 
was  composed  of  9  parts  of  tin  to  13  of  silver. 

I  had  noticed  the  wonderful  maintenance  of  integrity  on  the 
part  of  the  silver  coin  amalgam  fillings ;  and  though  I  then 
shared  the  prevailing  prejudice  against  the  copper  which  I 
knew  such  amalgam  to  contain,  I  was,  nevertheless,  compelled 
to  admit  the  loss  of  edge-strength,  the  greater  crevicing,  and 
the  general  inferiority  of  amalgam  made  from  the  largely  tin 
alloy.  For  this  reason  I  commenced  the  increase  of  silver,  and, 
notwithstanding  the  loss  in  the  direction  of  "  maintenance  of 
color,"  continued  its  addition  until  I  had  reached  a  decided  pre- 
ponderance of  that  metal. 

The  superficial  discoloration  had  long  since  lost  much  of  its 
power  to  stamp  the  filling  as  objectionable,  in  view  of  extended 
and  long-continued  proofs  of  capability  for  tooth  salvation ;  and 
even  the  objection  of  tooth  discoloration  had  been  thus  early 
largely  overcome  by  "lining." 

So  much  work  seemed  to  offer  in  other  lines,  and  so  urgently 
did  it  press  its  claims,  that  nothing  like  sufficient  attention  was 
bestowed  upon  alloys  for  amalgam  until  the  papers  upon  that 
subject  which  were  presented  at  the  meeting  of  the  New  York 
Odontological  Society,  held  in  December,  1874,  came  to  my 
notice.  These  I  read  with  the  greatest  interest  and  with  the 
most  critical  circumspection,  and  I  soon  found  that  I  must 


88  PLASTICS    AND     PLASTIC    FILLING. 

either  reconsider  the  whole  of  my  years  of  experimentation,  or 
take  decided  issue  with  the  evident  tendency  of  all  manufac- 
turers of  alloys. 

But,  again,  I  felt  that  I  must  receive  even  the  statements 
contained  in  those  papers  with  doubting  hesitation,  for,  with 
the  exception  of  the  experiments  and  conclusions  of  Dr.  S.  P. 
Cutler,  of  Memphis,  Tennessee, —  with  which,  in  the  main,  I 
could  agree, —  there  was  a  confused  mass  of  assertions,  experi- 
ments, analyses,  and  deductions,  which,  while  they  contained 
much  that  seemed  reasonable,  and  stated  some  facts  with  which. 
I  was  conversant,  yet  also  contained  so  much  that  was  conflict- 
ing or  of  doubtful  Value,  or  was,  in  my  opinion,  absolutely  in- 
correct, that  I  judged  it  to  be  for  the  most  part  a  questionable 
contribution  to  knowledge. 

I  found  reference  made  to  the  practical  experiments  of 
Messrs.  John  and  Charles  Tomes,  1861  to  1872,  which  I  had 
regarded  as  conclusive,  and  had  accepted  as  such.  I  found  the 
term  "  oxidation,"  as  almost  invariably  applied  to  the  discolor- 
ation of  amalgam  fillings,  corrected  by  the  acceptance  of  the 
lony  before  urged,  and  much  more  reasonable,  hypothesis  of 
"  sulphuretting."  I  found  confusing  statements,  such  as  an 
alloy  of  "  two  parts  silver,  one  part  tin,  and  about  twenty-five 
per  cent,  gold,"  which  would  be  simply,  two  silver,  one  tin,  and 
one  gold.  I  found  a  long  list  of  elaborate  experimentation  with 
filled  teeth  and  amalgam  pellets,  weighed  with  marvellous  ac- 
curacy, placed  in  little  bottles  containing  saliva  acidulated  with 
nitric,  acetic,  citric,  or  hydrochloric  acid,  and  kept  in  a  water- 
bath  inside  of  another  water-bath,  at  a  uniform  temperature  — 
blood-heat  —  for  a  period  of  three  months,  in  order  to  prove 
by  analysis  of  the  saliva  whether  or  not  amalgam  fillings  would 
be  capable  of  producing  mercurial  ptyalism. 

I  could  not  reasonably  doubt  the  certificate  of  the  "  Professor 
of  Analytical  and  Applied  Chemistry,"  that  the  saliva  "  contained 
no  mercury  in  solution ;  "  but  I  gravely  doubted  the  value  of 
the  test  as  proving  anything  whatever  in  relation  to  the  sys- 
temic influence  of  amalgam  fillings. 

I  found  analyses,  made  "  through  kindness,"  which,  although 
so  full  of  such  glaring  discrepancies  as  scarcely  to  deceive 
one  who  had  closely  observed  in  amalgam  work,  were  yet  so 


AMALGAM.  39 

speciously  presented  as  to  grossly  mislead  tlie  mass  of  inquirers, 
and  thus  prove  anything  but  a  "kindness"  to  them. 

In  these  the  information  was  given  that  "  Lawrence's  "  alloy 
had  in  it  nearly  fifteen  per  cent,  of  copper !  and  "  Townsend's 
Improved,"  which  sold  for  $2.00  per  ounce,  was  given  as  com- 
posed of  materials  —  silver,  tin,  and  gold  —  in  such  quantities 
a?  would  have  cost  81.80  per  ounce  for  these  alone! 

From  a  personal  acquaintance  with  the  dealers  in  alloys,  I 
thought  this  could  not  be  true. 

About  this  time  I  came  into  metalluryic  association  with  my 
friend,  Mr.  Patterson  Du  Bois,  one  of  the  assistant  assayers  of 
the  Philadelphia  "Mint ;  he  had  been  for  some  years  a  patient 
of  mine,  and  recognizing  the  deep  interest  which  I  took  in 
dental  alloys,  he  offered  to  make  for  me  a  series  of  analyses. 

I  eagerly  embraced  this  opportune  aid  to  investigation,  and  the 
work  was  commenced.  So  great  an  interest  upon  his  part  was 
soon  engendered,  that  he  asked  permission  to  add  the  power  of 
another  assayer  to  the  task  ;  thus  Mr.  Jacob  B.  Eckfeldt  became 
interested  with  us,  and  we  prepared  for  extensive  and  thorough 
manipulation.  The  incentive  then,  to  them,  was  the  probability 
of  eventually  arriving  at  an  excellent  alloy  which  they  could 
manufacture.  The  incentive  to  me,  was  the  evident  possibility 
of  so  directing  experimentation  as  to  secure,  promptly,  a  good 
result,  based  upon  some  reliable  data. 

This  I  felt  would  be  a  boon  to  my  profession,  my  patients, 
and  myself. 

Our  first  requirement  was  the  purchasing  and  analyzing  of 
one  or  more  samples  of  every  alloy  of  note  in  the  market.  It 
was  needful  that  caution  should  here  be  used  lest  attempts  should 
be  made  to  lead  us  astray.  It  was  recognized  that  manufacturers 
might,  very  properly,  regard  it  as  "  business  "  to  prepare  for  us 
special  samples,  if  it  was  known  that  we  purchased  expressly 
for  analysis ;  we,  therefore,  as  promptly  as  possible,  and  largely 
through  the  hands  of  other  parties,  obtained  the  desired  samples 
from  various  cities  and  countries ;  of  the  most  noted  we  ob- 
tained three  samples  each  at  various  times,  ranging  from  one  to 
three  months  apart. 

As  one  after  another  of  these  alloys  were  analyzed,  two  salient 
points  became  apparent ;  first,  that  the  analyses  given  in  the 


40 


PLASTICS    AND    PLASTIC    FILLING. 


paper  compiled  by  Prof.  T.  B.  Hitchcock,  and  presented  by- 
Prof.  T.  H.  Chandler,  at  the  New  York  "  Odontological  "  meet- 
ing of  December,  1874,  were  almost  entirely  unreliable,  and  emi- 
nently calculated  to  mislead  inquirers ;  and,  second,  that  with  but 
two  exceptions,  viz.,  the  alloys  of  Drs.  Lawrence  and  Hardman, 
all  the  other  alloys  in  the  market  were  based  upon  one  of  two 
ideas,  viz.,  some  regarded  the  addition  of  small  quantities  of 
gold  and  platinum  as  essentially  advantageous,  and  others  did 
not ;  but  practically  all  agreed  that  the  proportions  of  tin  and 
silver  should  be  from  fifty-five  to  sixty-five  per  cent,  of  tin,  and 
from  thirty-five  to  forty-five  per  cent,  of  silver. 

As  examples  in  proof  of  these  positions  I  offer  the  follow- 
ing half-dozen  analyses : 


ANALYZED  BY  DR.  E.  S.  WOOD, 
PROFESSOR  OF  CHEMISTRY  IN 
HARVARD  MEDICAL  AND  DEN- 
TAL SCHOOLS. 

"  Townsend's." 

Silver 40.21 

Tin 47.54 

Copper     ....    10.65 
Gold 1.06 

"Arlington's." 

Silver 40.00 

Tin 60.00 

"Walker's." 

Silver 34.89 

Tin 60.01 

Gold 4.14 

Platinum      ...  .96 

"  Townsend's  Improved." 

Silver 39.00 

Tin 55.69 

Gold 5.31 

"Lawrence's." 

Silver 47.87 

Tin 33.68 

Copper     ....     14.91 
Gold  3.54 


ANALYSES  BY  MESSRS.  ECKFELDT 
AND  D0  Bois,  METALLURGIO 
SECTION  OF  THE  "NEW  DE- 
PARTURE CORPS." 

"  Townsend's." 

Silver 42.00 

Tin  .     .     .   ..     .     .     58.00 

Copper,  none. 
Gold,  none. 

"  Arrington's." 

Silver 42.50 

Tin 57.50 

"Walker's." 

Silver 30.50 

Tin 69.00 

Platinum      ...        .50 
Gold,  none. 

"  Townsend's  Improved." 

Silver 43.00 

Tin 57.00 

Gold,  none. 

"  Lawrence's. 

Silver 47.50 

Tin 47.50 

Copper     ....      5.00 
Gold,  a  trace  (ri^th  gr.) 


AMALGAM.  41 

"  Johnson  &  Lund."  "  Johnson  &  Lund." 

Silver 38.27  Silver 38.50 

Tin 59.58  Tin 59.40 

Platinum      .     .     .       1.34  Platinum      ...         .40 

Gold 81  Gold 60 

Cadmium  not  mentioned.  Cadmium     .     .     .       1.06 

As  I  had  experimented  in  the  mouth  with  nearly  every  alloy 
analyzed,  and  was  thus  conversant  with  the  working  qualities, 
the  defects,  and  the  advantages  of  each,  it  required  but  a  few 
weeks  to  make  the  necessary  deductions  for  the  initial  alloy. 
Regarding  the  average  proportions  of  tin  and  silver,  in  nearly 
all  the  alloys  manufactured,  as  60  tin  and  40  silver,  and  inform- 
ing my  co-laborers  of  the  advantages  which  I  had  noted  in  the 
increase  of  silver,  we,  after  nine  preliminary  experiments,  in- 
verted the  proportions,  and  commenced  with  60  silver  and  40 
tin ;  and  it  is  with  much  satisfaction  that  I  can  say,  that  five 
years  of  experiment  and  observation,  done,  as  we  believe,  with 
itnbiased  care  and  accuracy,  has  only  strengthened  our  convic- 
tions that  these  basal  proportions  —  modified  by  additions  of 
copper,  gold,  and  zinc;  possibly  antimony;  more  doubtfully, 
platinum;  and  most  doubtfully,  cadmium  —  will  constitute  the 
best  alloys  for  amalgam  fillings  which  can  be  made /row  the 
metals  that  are  now  accepted  as  components  for  such  alloys. 

At  this  point,  I  desire  to  enter  a  protest  against  the  tendency 
to  mislead,  which  is  found  in  names  and  statements  pertaining 
to  alloys,  as  I  regard  the  tacit  acceptance  of  them  by  dentists 
as  a  reproach  to  dentistry. 

Every  "gold  and  platiua  "  alloy  in  the  market  is,  at  present, 
composed  of  more  than  fifty  per  cent,  of  tin,  and  more  than  forty 
per  cent,  of  silver,  while  the  remaining  few  per  cent. — two  to 
seven,  only — are  found  to  be  of  gold  and  platinum.  Now,  as 
the  addition  of  a  small  proportion  of  gold  in  connection  with  so 
larye  a  proportion  of  tin,  even  though  it  be  in  sliyht  deyree  ad- 
vantageous; and  as  the  addition  of  platinum,  either  in  small 
or  large  proportions,  is,  as  yet,  not  proven  to  be  of  any  benefit, 
but  must  be  ranked  as  of  "  doubtful "  utility,  these  so-called 
"  gold  and  platina  ''•  alloys  cannot  be,  in  much  degree,  superior 
to  the  ordinary  alloys  of  tin  and  silver.  I  therefore  submit  the 
proposition,  that,  both  in  name  and  inference  of  great  superior' 


42  PLASTICS    AND    PLASTIC    FILLING. 

ity,  these  alloys  are  deceptive,  and  their  acceptance  is  deroga- 
tory to  the  intelligence  of  dentistry. 

Many  alloys  are  constantly  advertised  with  the  assertions  of 
"no  shrinkage"  and  "no  discoloration,"  when  the  truth  is  that 
fillings  made  from  them  both  "  shrink  "  and  "  discolor  "  most 
notably ;  and  those  that  shrink  least,  as  a  rule,  with  very  rare 
exceptions,  discolor  most ;  while  those  that  discolor  least,  as  a 
rule,  shrink  most !  Alloys  are  constantly  appearing  which  are 
advertised  as  "  superior,"  as  "  best,"  as  "  made  by  a  new  proc- 
ess," etc.,  which,  upon  analysis,  are  found  to  be  composed  of 
the  same  ingredients,  in  the  same  proportions,  as  have  been 
almost  universally  used ;  their  "plasticity,"  their  "  setting,"  their 
"  edge-strength,"  their  "  shrinkage,"  their  "  color-tests,"  are  all 
exactly  the  same  with  the  other  average  alloys,  and  yet  each 
has  a  long  list  of  "  testimonials  "  as  to  its  superior  peculiarities 
from  gentlemen  who  are  regarded  as  eminent  in  our  profession. 

NOTE.  —  During  the  session  of  the  American  Dental  Association  at  Niagara 
Falls,  in  1878  —  only  two  years  since —  I  was  told  by  one  of  the  prominent  dele- 
gates that  he  preferred  decidedly  the  "  Arrington"  alloy  to  that  which  was  sold 
as  "  Townsend's ; "  and  upon  asking  him  "Why?"  the  reply  was,  "because  it 
works  much  more  plastic,  sets  much  quicker,  makes  better  edges,  keeps  its  color 
better,  and  altogether  makes  a  much  better  filling  "  I  could  hardly  credit  my  own 
hearing !  for  I  knew,  from  analyses,  from  working,  from  careful  testing,  and  from 
many  observations  in  the  mouth,  that  the  two  alloy?,  as  compounded  and  cut, 
were  precisely  the  same,  and  that  the  only  difference  between  them  was  that  of 
size  of  grain. 

It  is  a  satisfaction  to  know  that  this  kind  of  thing  must  pass 
away  in  due  time.  Already  the  advanced  collegiate  instruction 
provides  students  with  the  needful  information,  both  theoretic 
and  practical,  in  the  direction  of  testing  and  analyzing  alloys 
which  are  offered  for  sale,  and  also  with  instruction  in  the  com- 
pounding and  making  of  all  such  alloys  and  other  materials  for 
plastic  filling  as  have  been  proven,  by  competent  testing,  worthy 
of  confidence. 

Already  the  young  men  go  into  the  field  of  practice  so  much 
better  "  armed  and  equipped,"  in  relation  to  these  matters  of 
vital  interest  and  importance,  that  they  are  self-dependent,  and 
can  far  better  instruct  than  be  instructed  by.  those  whose  expe- 
rience in  plastics  has  been  guided  by  "judgment''  rather  than 
by  knowledge. 


METALS    USED    FOB    AMALGAM    ALLOYS.  43 


AETICLE   V. 

ATTRIBUTES  OF  METALS   USED  FOE  AMALGAM 
ALLOYS. 


or  more  metals  combined  by  melting  form  an  "  alloy." 
-  One  or  more  metals  held  in  combination  with  mercury, 
by  the  mercury,  form  an  "  amalgam.'' 

This  is  the  dental  acceptation  of  these  terms  ;  and  we  there- 
fore find  "alloys,"  containing  mercury  in  very  small  proportion, 
added  for  the  purpose  of  making  them  more  fusible  ;  but  no 
mixture  of  metals  is  regarded  as  an  "  amalgam  "  unless  it  has 
mercury  as  one  of  its  components  in  sufficient  quantity  to  ex- 
ert a  combining  influence  over  the  other  metals. 

Our  present  theory  regarding  the  formation  of  amalgam  is, 
that  metals  which  melt  at  comparatively  high  temperatures, 
being  so  prepared  as  to  permit  of  the  fusing  influence  of  mer- 
cury, —  a  metal  which  is  "molten"  even  at  very  low  tempera- 
ture (  —  30°),  —  are,  by  admixture  with  mercury,  melted  into 
union  with  it.—  Du  Bois. 

The  acceptance  of  this  theory  not  only  seems  to  simplify 
the  otherwise  complex  and  mysterious  behavior  of  this  pecu- 
liar filling-material,  but  aids  much  in  the  accurate  construction 
of  various  alloys  with  the  view  to  accomplish  specific  purposes. 

Thus,  the  "setting"  of  the  amalgam  —  as  the  gradual  hard- 
ening of  the  mass  is  technically  termed  —  is  recognized  as  due 
to  the  secondary  cooling  influence  upon  the  mercury  from  mix- 
ture of  such  metals  as  are  not  molten  at  ordinary  temperature  ; 
and  it  is  readily  appreciated,  —  at  least,  in  a  general  way,  —  that 
the  higher  the  melting-point  of  the  admixed  metal,  the  quicker 
will  be  the  "  setting." 

I  say,  "  in  a  general  way,"  for  it  is  practically  demonstrated 
—  by  platinum  —  that,  in  some  way,  —  from  physical  charac- 
teristics, —  a  metal  even  of  very  high  melting-point  may  not 
produce  this  result;  but  this  is  exceptional. 

The  decided  "bulging"  —  as  the  spheroidiny  of  the  mass  is 
termed  —  of  fillings  made  of  alloys  largely  composed  of  tin, 
may  be  plausibly  attributed  to  the  combined  ductility  and  low 
melting-point  of  the  admixed  metal.  Under  the  strong  con- 


44  PLASTICS    AND    PLASTIC    FILLING. 

trol  of  a  rapidly  and  rigidly  hardening  metal,  this  spheroiding 
is  found  to  be  limited;  under  the  feeble  control  of  a  metal 
which  cools  slowly,  and  when  cold  is  yielding,  the  gradual 
spheroiding  continues  for  many  months,  and  even  years,  until 
it  eventuates  in  excessive  "  bulging." 

The  "  shrinking  "  of  the  mass  is  also  in  general,  though  not 
in  universal  accord  with  the  contraction  of  the  metals  com- 
posing it,  as  they  pass  from  the  fluid  to  the  solid  state.  Thus, 
tin,  losing  its  fluidity  slowly,  permits  shrinkage  in  proportion 
as  it  is  added  in  quantity.  Gold  and  copper,  which  lose  fluid- 
ity quickly,  and  silver,  which  expands  in  cooling,  notably 
lessen  shrinkage.  Platinum  —  by  far  the  most  obdurate  of 
metals  used  in  dental  alloys  —  seems  to  exercise  such  imper- 
ceptible control  over  shrinkage  as  to  be  unworthy  of  mention 
in  this  connection. 

The  "  plasticity  "  of  an  amalgam,  using  the  term  as  applied 
to  the  length  of  time  during  which  it  may  be  worked,  as  "  it 
remains  plastic  for  fifteen  or  twenty  minutes,"  is  almost  entirely 
in  consonance  with  the  relative  proportion  of  the  easily  melted 
tin ;  but  here  again  we  find  platinum  increasing  this  peculiarity, 
and  even  in  some  alloys  maintaining  a  plastic  condition  in  a 
most  undesirable  degree. 

The  "  edge-strength  "  of  amalgam  is  singularly  influenced  by 
the  ratio  of  edge-strength  of  its  components,  as  compared  with 
their  melting-points ;  thus,  some  metals  which  have  little  edge- 
strength  and  melt  at  low  temperatures,  as  tin,  require  to  be 
mixed  in  large  proportion  in  an  alloy  before  they  will  seriously 
impair  the  edge-strength  of  an  amalgam ;  while  some  metals 
which  have  fair  edge-strength  and  require  a  high  temperature 
for  their  melting,  as  copper,  in  comparatively  small  proportion 
of  admixture,  will  markedly  impair  the  edge-strength  of  amal- 
gam ;  metals  which  have  reasonably  good  edge-strength  and 
melt  at  high  temperatures,  as  silver,  add  reasonably  to  the  edge- 
strength  of  amalgam  as  their  relative  proportion  in  an  alloy  is 
increased  reasonably  ;  other  metals  of  fair  edge-strength  which 
melt  at  high  temperature,  as  gold,  add  notably  to  the  edge- 
strength  of  amalgam,  especially  that  made  from  largely  silver 
alloys,  even  though  added  in  but  small  quantity  to  the  alloy. 

In  effect  upon  edge-strength  platinum  seems  to  be  entirely 


METALS    USED    FOR    AMALGAM    ALLOYS.  45 

neutral,  whether  added  in  small  or  large  quantity.  This  was 
tested  in  amalgams  made  from  alloys  containing  platinum  in 
varying  quantity,  from  less  than  one  per  cent,  to  more  than  five 
per  cent. 

The  "hardness"  or  "density"  of  amalgam  seems  to  depend 
entirely  upon  the  toughness  of  the  metals  composing  the  alloy. 
This  is  a  point  which  would  require  a  vast  amount  of  experi- 
mentation to  establish ;  an  amount  which,  at  present,  would  be 
non-compensating,  for  the  reason  that  we  have  no  difficulty  in 
making  amalgam  of  sufficient  density.  Indeed,  if  we  could  im- 
prove in  the  direction  of  "  maintenance  of  color  "  without  in- 
crease of  "  shrinkage,"  and  without  loss  of  "  edge-strength," 
but  by  diminishing  in  "  density,"  it  would  be  rather  beneficial 
than  detrimental,  for  even  the  least  desirable  of  all  the  alloys, 
Townsend's,  Walker's,  Arrington's,  etc.,  are  more  than  suffi- 
ciently "dense"  to  subserve  all  practical  purposes. 

NOTE.  —  The  terms  "hard"  and  "dense,"  though  not  synonymous  in  metal- 
lurgy, seem  to  have  become  such  in  the  technical  phraseology  of  amalgam  alloy 
work  ;  they  are  used  as  opposite  to  "  soft,"  while  the  term  "  brittle  "  is  employed 
as  indicative  of  another  characteristic  which  may  pertain  either  to  soft  or  hard 
amalgam,  it  meaning  easy  to  be  broken  or  crushed. 

The  metals  which  are  at  present  used  in  alloys  for  dental 
amalgams,  are,  silver,  tin,  copper,  gold,  zinc,  antimony,  cadmium, 
and  platinum. 

NOTE.  —  Palladium,  tellurium,  etc.,  are  not  included  in  this  list,  because  the 
several  reasons,  that  the  very  high  price  of  the  metals  —  from  thirty-five  to  fifty 
dollars  per  ounce  —  the  great  difficulty  of  obtaining  them  in  adequate  quantity 
and  the  decidedly  theoretic  value  yet  pertaining  to  them  as  components  of  amal- 
gam alloys,  were  deemed  sufficient  to  deprive  work  upon  them  of  all  practical 
value,  at  least  so  far  as  pertains  to  present  demands. 

SILVER.  Aryenium.  Symbol,  AG.  Fuses  at  1873°  F.  Ex- 
pands on  cooling. 

As  in  1826,  under  the  auspices  of  M.  Taveau,  the  name  of 
"  silver  paste  "  was  given  to  the  prototype  of  that  filling  ma- 
terial now  known  as  "  amalgam,"  so  might  it  reasonably  be 
given  to  all  the  amalgams  of  the  present  day. 

Silver  is  the  first,  the  most  important,  the  essential  metal  of 
a  good  amalgam  alloy  for  filling  teeth  ;  it  is  the  largest  compo- 


46  PLASTICS    AND. PLASTIC    FILLING. 

nent  of  every  truly  good  "  submarine,"  "  usual,"  or  "  contour  " 
alloy  in  the  market ;  and  it  will  be  found  by  all  actual  tests, 
that  just  in  proportion  as  an  alloy  contains  silver  in  small 
amount,  so  will  it  make  an  amalgam  which  will  not  compare 
favorably,  in  its  meeting  of  almost  every  dental  requirement, 
with  those  made  from  alloys  which  are  largely  composed  of  this 
metal. 

The  most  ordinary  amalgams  of  to-day,  taking  that  made 
from  "  Townsend's "  alloy,  60  tin,  40  silver,  as  the  type,  are 
mixed  into  pastes,  with  about  two-fifths  their  weight,  con- 
sisting of  mercury,  a  little  less  than  two-fifths  tin,  and  a  little 
more  than  one-fifth  silver,  38  parts  mercury,  39  parts  tin,  23 
parts  silver  =  100  parts ;  and  yet  the  silver  is  the  essential,  for 
without  it  the  amalgam  would  be  worthless  for  filling  teeth.  In 
the  next  grade  of  alloys  are  those  composed  of  the  same  relative 
proportions  of  tin  and  silver,  but  with  the  additions  of  gold  or 
gold  and  platinum. 

In  these  the  silver  is  still  the  essential ;  but  in  the  endeavor 
to  keep  its  proportion  small,  and  to  overcome,  by  the  addition 
of  the  other  metals,  the  loss  of  edge-strength  and  the  tendency 
to  shrink  and  bulge  incident  to  large  admixture  of  tin,  it  is 
found  that  something  is  yet  required  to  meet  the  emergency; 
and  it  is  therefore  proposed,  by  the  manufacturers  of  such  alloys, 
that  they  be  mixed  with  the  smallest  possible  amount  of  mer- 
cury, be  worked  in  the  form  of  a  "kind  of  powder,"  and  be 
made  into  amalgam  by  packing  into  the  cavity  with  warm  in- 
struments. 

With  the  next  grade  of  alloys  the  stereotyped  proportions  of 
tin  and  silver  are  inverted,  of  these  the  "  old  reliable  "  alloys 
of  Hardman  of  Muscatine,  Iowa,  and  Lawrence  of  Lowell, 
Mass.,  are  the  types ;  but  in  these  we  find  the  valuable  admix- 
ture of  copper  in  addition  to  the  increased  proportion  of  silver. 

Any  operator  who  has,  for  many  years,  wrought  faithfully 
with  these  alloys,  has  found  no  need  for  "  dry  powder  "  in  place 
of  well  constituted  plastic  "amalgam,"  nor  has  he  had  to  heat 
his  instruments  in  order  to  introduce  his  fillings  ;  and  I  am  sure 
that  each  can  point  to  many  a  monument  of  "  capability  for 
tooth  salvation,"  even  in  desperate  cases,  which  is  alike  a  marvel 
to  himself  and  to  his  patients ;  and  these  results,  both  that  of 


METALS    USED    FOR    AMALGAM    ALLOYS.  47 

possibility  of  easy  working,  and  that  of  eminence  in  tooth- 
saving,  are  due,  almost  exclusively,  to  the  large  proportion, 
relatively,  of  silver. 

Again,  with  progressing  gradation,  we  reach  the  present  high- 
est type  of  "usual"  alloys,  composed  of  silver,  tin,  gold,  and 
copper,  and  represented  by  the  very  properly  named  "  Stand- 
ard" alloy  of  Eckfeldt  and  Du  Bois. 

NOTE.  —  Having  been  reliably  informed  that  it  has  been  reported,  with  invid- 
ious comments,  that  I  have  a  pecuniary  interest  in  the  sale  of  "  Standard  "  alloy, 
I  would  say  that,  while  I  cannot  see  the  impropriety  of  holding  such  interestf 
if  I  held  it,  the  statement  is  entirely  untrue ;  and  that  I  have  never  had  any 
other  business  relations  with  Messrs.  Eckfeldt  and  Du  Bois  than  those  of  a  purely 
experimental  character. 

So  far  from  deriving  any  pecuniary  benefit  from  the  sale  of  this  alloy,  I  ex- 
pended my  third,  of  nearly  seven  hundred  dollars,  in  the  work  of  developing  the 
basal  deductions  which  eventuated  in  the  material  that  has  been  offered,  with  its 
gradual  mutations,  year  by  year,  to  the  profession,  and  of  which  it  is  truthfully 
said  that,  "  acting  as  a  pioneer,  the  '  Standard'  has  literally  established  a  stand- 
ard; "  and  I  also  wish  to  say,  that  I  would  willingly  have  contributed  hundreds 
of  dollars  more,  had  it  been  needed,  for  the  satisfaction  which  I  have  enjoyed  in 
the  possession  of  that  solid  substratum  of  information  in  regard  to  dental  amal- 
gam alloys  which  I  feel  has  been  of  so  much  value  to  me  and  mine,  and  which  I 
think  I  could  not  have  as  well  obtained  from  any  other  source. 

In  these  we  find  the  relative  importance  of  the  silver  even 
more  fully  recognized ;  and  while  we  cannot  regard  them  as 
superior  to,  if  even  equal  with,  the  three  metal  alloys,  when 
viewed  merely  as  tooth  preservers,  we  yet  cannot  deny  to  them 
the  possession  of  sharper  and  stronger  edges ;  greater  rapidity 
of  setting;  finer  plasticity  in  working;  and  a  better  general 
maintenance  of  color. 

To  the  silver,  then,  we  ascribe  the  position  of  metal  of  first 
importance  ;  it  is  essential  to  the  proper  setting  of  the  amalgam; 
it  notably  maintains  the  bulk  integrity  of  the  filling,  and  it 
forms,  with  the  sulphuretted  hydrogen,  which  is  more  or  less 
constantly  brought  into  contact  with  it  in  the  mouth,  sulphide 
of  silver,  which,  though  it  discolors  the  filling  and  also  the 
tooth,  is  nevertheless  highly  conducive  to  the  permanent  saving 
of  teeth  which  are  not  only  largely  decayed,  but  markedly  pre- 
disposed to  continued  decay. 

Tix.     Stannum.     Symbol,  SN.     Fuses  at  442°  F. 


4:8  PLASTICS    AND    PLASTIC    FILLING. 

I  have  placed  this  metal  second  on  the  list,  because,  although 
it  is  a  component  of  comparatively  modern  introduction,  and 
is  largely  ante-dated  by  copper,  and  although  its  introduction 
well-nigh  ruined  a  material  which  had  bravely  withstood  the 
assaults  of  unscrupulous  prejudice  for  more  than  a  quarter  of  a 
century,  it  has  at  length,  by  long  and  elaborate  experiments, 
been  assigned  a  position  in  which,  under  control,  it  becomes 
the  second  in  importance  upon  the  grounds  of  quantity  and 
usefulness. 

All  such  alloys  as  I  should  favorably  regard,  have  from  35 
to  48  per  cent,  of  tin ;  it  is  found  that  by  the  addition  of  copper 
and  gold,  both  antagonists  of  "  shrinkage,"  the  most  deleteri- 
ous of  the  effects  of  tin  can  be  counterbalanced;  that  under  this 
control  sufficient  silver  can  be  used  to  obviate  a  detrimental 
loss  of  edge-strength;  that  the  retardation  of  "setting"  is  pre- 
vented, and  that  the  tin  not  only  loses  its  power  for  harm,  but 
becomes  an  ingredient  of  manifold  utility  ;  it  greatly  augments 
the  facility  of  amalgamation ;  it  aids  in  producing  a  good  color 
and  in  preventing  discoloration;  and  it  diminishes  conduc- 
tivity. 

COPPEE.     Cuprum.     Symbol,  Cu.     Fuses  at  1996°  F. 

The  "  Royal  Mineral  Succedaneum "  was  an  amalgam  of 
mercury,  silver,  and  copper  ;  it  was  made  from  silver-coin  filings 
which  were  composed  of  an  approximate  to  nine-tenths  silver 
and  one-tenth  copper ;  the  amalgam  was  made  by  mixing  about 
equal  parts  of  mercury  and  filings ;  the  result  was  a  mixture 
consisting  of  50  parts  mercury,  45  parts  silver,  5  parts  copper 
=  100  parts. 

This  material  saved  teeth  even  though  abused  and  misused, 
but  its  surface  discolored  outrageously, — it  darkened  teeth 
abominably, — and  the  soluble  salts  of  the  uncontrolled  copper 
in  fillings  entering  pulp  cavities  and  canals,  so  permeated  the 
dentine  and  ccmentum,  coloring  them  a  livid  green,  as  to  give 
rise  to  a  warrantable  suspicion  that  to  the  presence  of  this 
metal  might  be  attributed  the  subsequent  death  and  exfoliation 
of  such  teeth. 

NOTE.  —  As  I  cannot  but  admire  the  ingenious  reasoning  of  Mr.  Tomes  in  re- 
gard to  this  form  of  discoloration,  I  quote  from  him : 

"  The  sulphide  of  copper,  under  the  influence  of  exposure  to  air  and  moisture, 


METALS     USED    FOR    AMALGAM    ALLOYS.  49 

readily  becomes  oxidized,  and  forms  the  sulphate.  Hence  it  is  almost  certain  we 
shall  have  sulphate  of  copper  formed  upon  the  exposed  surface  of  the  filling.  Now 
this  sulphate  is  freely  soluble,  and  hence  is  likely  to  permeate  the  dentine,  when  it 
will  again  be  converted  into  sulphide,  whilst  the  sulphides  of  other  metals,  not 
being  so  readily  converted  into  soluble  salts,  will  not  so  thoroughly  permeate  the 
teeth." 

For  this  reason  copper  was  early  looked  upon  as  a  very 
objectionable  ingredient  of  amalgam,  and  "virgin  silver"  was 
the  first  desideratum  ;  but  I  have  constantly  noticed,  during  all 
the  many  years  in  which  my  professional  brethren  in  our  own 
country  have  been  reaping  the  harvest  of  a  fearful  loss  of  soft 
teeth,  under  the  regime  of  elegant  gold-work,  and  have  been 
vainly  endeavoring  to  stay  the  tide  of  destruction  by  an  in- 
crease of  the  already  lavish  incorporation  of  tin  in  amalgam, 
that  my  professional  brethren  in  other  countries,  particularly 
England,  have  been  saving  just  such  teeth  by  using  amalgam, 
of  which  copper  was  a  component ;  and  that  in  some  of  these 
filling  materials  this  metal  abounded  in  marvellous  quantity ; 
thus  it  was  that,  as  I  was  continually  lessening  the  ////,  and  in- 
creasing the  silver,  in  my  efforts  to  save  the  teeth  which  had 
become  wrecks  from  being  repeatedly  filled  with  gold,  I  began 
thinking  favorably  of  the  despised  and  discarded  copper. 

I  was  not  alone  in  this,  for  others  seemed  so  evidently  im- 
pressed with  the  value  of  the  diminishing — silver — and  aban- 
doned— copper — metals,  that  the  heavily  silvered  three-metal 
alloys  were  produced.  It  is  one  of  the  peculiarities  of  the 
"judgment"  practice,  that  hundreds  of  practitioners  have,  for 
a  long  time,  used  Lawrence's  and  Hardman's  alloys  with  most 
satisfactory  results  to  themselves  and  to  their  patients,  who 
would  have  been  horror-stricken  if  their  "  knowledge  "  had  told 
them  that  each  contained  copper  ! 

NOTE.  —  It  is  but  little  more  than  one  year  since  a  paper  upon  the  subject  of 
"amalgams"  was  read  by  a  Professor  of  Denial  Metallurgy,  from  which  I  quote: 
"  Most  dentists  would  hesitate  about  employing  an  amalgam  known  to  contain 
copper;  yet  I  was  much  surprised  recently  (!)  at  the  result  of  a  careful  analysis 
of  an  amalgam  filling  which  had  done  good  service  for  twenty-three  years,  dur- 
ing which  period  it  had  retained  a  perfectly  bright  and  smooth  surface  exteriorly. 
.  .  T  found  its  composition  —  after  freeing  from  mercury  —  to  be  tin,  55  parts; 
silver,  40  parts;  copper,  5  parts." 

From  an  educational  point  of  view,  it  seems  sad  that,  at  this  late  day,  a  teacher 
of  dental  metallurgy  should  have  been  thus  "  surprised." 
4 


50  PLASTICS    AND    PLASTIC    FILLING. 

But  it  is  not  alone  the  marked  compatibility  of  these  par- 
tially copper  amalgams  with  tooth-bone  which  characterizes 
them  as  peculiar ;  for  it  has  also  been  noted,  and  commented 
on,  that  pulps  seem  to  evince  decided  toleration  for  them.  It 
has  been  my  own  experience  in  practice,  that  teeth,  in  which 
"  deep  "  and  "  very  deep  "  cavities  of  decay  had  been  filled  with 
amalgams  containing  copper,  have,  as  a  rule,  behaved  better 
than  those  which  had  been  filled  with  amalgams  which  did  not 
contain  this  metal.  My  record  of  pulp-saving — noted  in  each 
case  after  five  years  of  trial — is  very  significant  in  its  connec- 
tion with  the  presence  of  a  portion  of  copper ;  for,  while  I  do 
not  presume  to  say  that  it  is,  as  yet,  proven  beyond  question 
that  pulps  do  maintain  their  vitality  better  under  amalgam 
fillings  which  contain  copper  than  under  those  which  do  not, 
I  must  nevertheless  admit  that  observation  has  seemed  to  point 
so  conclusively  in  this  direction,  that  I  should,  in  my  practice, 
permit,  with  the  exception  of  tin,  no  metal  filling  which  did 
not  contain  copper  to  approach  a  pulp. 

And  yet  another  direction  in  which  copper  seems  useful  as 
an  adjunct,  is  its  singular  properties  as  alloyed  with  tin — the 
alloys  of  tin  and  copper  —  "  hard  brass  ;  "  "  bronze"  may  prop- 
erly be  regarded  as  among  the  most  curious  of  metallic  mix- 
tures. From  these  soft  and  yielding  metals  are  compounded 
some  of  the  best  alloys  for  brass  ordnance ;  the  unyielding 
"anti-frictions,"  and,  even  more  peculiar  still,  the  obdurate 
"speculum  metal." 

Very  iclnte  alloys  result  from  admixture  of  copper  with  tin, 
and  this  effect  is  noted  in  amalgam ;  by  proper  manipulation — • 
which  will  be  given  in  place  —  the  face  of  such  an  amalgam 
filling  can  be  finished  with  exceeding  wliiten ess  ;  and  although  I 
cannot  but  think  that  in  certain  mouths  the  presence  of  the 
copper  tends  much  toward  increasing  discoloration,  yet,  the 
usual  result,  particularly  under  the  controlling  influence  of  an 
addition  of  gold,  is  the  making  of  very  light-colored  fillings, 
which  retain  their  color  remarkably  well. 

To  copper,  then,  is  ascribed  the  power  of  diminishing,  in  a 
manner,  "shrinkage,"  as  copper  amalgam  neither  expands  nor 
contracts ;  it  favors  rapidity  of  "setting;"  it  is  accredited  with 
power  to  add  to  the  "  compatibility  "  of  the  filling  material 


METALS    USED    FOR     AMALGAM     ALLOYS.  51 

with  tooth-bone,  and  thus  better  saves  the  teeth ;  it  is  thought 
to  produce  greater  harmony  between  filling  material  and  dental 
pulp,  and  thus  promotes  "  toleration  "  of  foreign  material,  in 
close  proximity,  on  the  part  of  that  organ ;  it  adds  to  the  im- 
mediate whiteness  of  the  amalgam,  while  its  tendency  to  gradual 
discoloration  is  notably  under  control ;  for  these  reasons  I  re- 
gard it  as  a  most  valuable  component  of  dental  amalgams. 

GOLD.     Aurnm.     Symbol,  Au.     Fuses  at  2016°  F. 

This  metal  is  one  of  those  more  recently  added  to  the  list  as 
an  ingredient  of  dental  amalgam  alloys ;  it  has  been  but  very 
few  years  —  eight  or  ten  —  since  systematic  experiments  with 
it  were  inaugurated ;  opinions  are  yet  varied  in  regard  to  some 
of  its  effects  upon  amalgam,  but  enough  are  in  unison  to  show 
that  it  is  worthy  of  place  in  our  considerations,  while  the  con- 
cluding work  of  the  "New  Departure  Corps  "  left  it  with  me, 
so  far  as  its  possibilities  are  concerned,  in  the  position  of  the 
most  undetermined  element. 

In  relation  to  its  effect  upon  "  shrinkage,"  there  can  be  but 
one  opinion ;  the  "  specific  gravity  "  work  of  Dr.  C.  S.  Tomes 
established  not  only  the  fact  of  its  prevention  of  shrinkage,  but 
the  ratio  of  its  preventive  power ;  but  opinions  concerning  its 
control  of  color,  and  particularly  its  control  of  "  setting  "  and 
"density,"  are  antagonistic  in  the  extreme. 

In  the  paper  of  Prof.  Hitchcock  (Harvard  Dental  Depart- 
ment), it  is  stated  that  an  English  alloy  of  (/old  one  part,  tin  two 
parts,  silver  three  parts,  is  said  to  keep  its  color  well,  but  does  "  not 
become  very  hard}'1  And  again,  he  says,  "Gold  does  not  harden 
well  with  mercury.  When  added  to  an  amalgam  of  silver  and 
tin,  however,  it  produces  a  decided  effect  in  lessening  not  only 
the  shrinkage,  but  also  the  tendency  to  ball  up  and  round  itself 
in  the  angles;  but  while  .it  does  this,  it  greatly  retards  the  set- 
tint/." 

The  Professor  of  Dental  Metallurgy,  of  University  of  Penn- 
sylvania Dental  Department,  states  that  he  found  an  alloy  of 
gold  one  part,  silver  four  parts,  tin  five  parts, —  as  simplified 
from  his  "  two  thousand  five  hundred  milligramme  "  arrange- 
ment,—  when  mixed  with  half  its  weight  of  mercury  "retained 
its  sharpness  of  edge,  hardened  well  in  a  few  minutes,  and  ap- 
parently filled  all  the  requirements  of  a  dental  amalgam." 


52  PLASTICS    AND    PLASTIC    FILLING. 

At  first  sight  the  discrepancy  of  these  statements  is  confusing, 
but  a  closer  examination  renders  them  even  more  so.  Beduc- 
ing  the  "  parts  "  of  the  two  alloys  to  the  usual  analytical  "  hun- 
dredths,"  for  the  purpose  of  easy  comparison,  we  find  them  to 
be,  practically, 


Gold  .  .  17 
Tin  .  .  33 
Silver  .  ,  50  f 


which  "does  not  become  very  hard,"  and  in  which  gold 
"greatly  retards  the  setting," 
100  j 

and 


Gold 

Silver  __ 

which  "  hardens  well  in  a  few  minutes," 


From  an  immense  experience  in  the  making,  testing,  and 
working  of  amalgam  alloys,  I  should  infer  that  the  state- 
ment of  Prof.  Hitchcock  was  largely  based — as  he  intimates 

—  upon  hearsay;  while  the  other  statement  is  evidently  based 
upon  actual  experiment ;  and  yet  the  two  statements  are  emi- 
nently calculated  to  mislead,  and   especially  when  contrasted 
as  we  have  them  above;  for  it  would  naturally  be  inferred  that 
the  second  formula,  in  regard  to  which  it  is  said  that,  when 
properly  mixed,  it  "apparently  filled  all  the  requirements  of  a 
dental  amalgam,"  must  be  decidedly  the  better  of  the  two ; 
while  the  facts  are  that,  when  properly  mixed,  the  supposed 
"English  amalgam  "  is  much  superior  to  the  other.     It  "sets" 
just  as  quickly;   gives  as  good  a  "color-test," — maintenance 
of  color   in   dilute   sulphuretted    hydrogen   wrater ;  —  hardens 
with  greater  density;  permits  of  finer  cutting,  and  "works" 
with   greater   smoothness;    has   less  "shrinkage"  and  better 
•"  edge-strength,"  and  yet  it  does  not  "  fill  all  the  requirements 
of  a  dental  amalgam." 

NOTE.  —  I  think  Prof.  Hitchcock  must  have  been  entirely  misinformed  re- 
garding the  alloy  to  which  he  has  referred ;  for  I  do  not  know  of  any  such  ma- 
terial, and  I  do  not  think  it  likely  that  anything  so  peculiar  —  if  in  the  market 

—  could  have  escaped  my  notice.     The  "first  cost"  of  such  an  alloy  would  be  at 
least  four  dollars  per  ounce  in  the  ingot.     The  addition  of  the  manufacturers' 
and  dealers'  profits  almost  always  makes  the  retail  price  treble,  and  sometimes 
more  than  quadruple,  the  amount  of  "  first  cost ; "  and  such  an  alloy  would  not, 


METALS     USED    FOR    AMALGAM     ALLOYS.  53 

therefore,  be  sold  for  less  than  ten  dollars  per  ounce.     So  far  as  I  know,  there  is 
none  such  advertised. 

From  our  line  of  experiments  it  lias  been  concluded  that 
gold,  more  than  any  other  metal,  in  proportion  to  the  small 
amount  required,  diminishes  "  shrinkage,"  increases  rapidity  of 
"setting,"  imparts  fine  grained  plasticity,  controls  "mainte- 
nance of  color,"  and  secures  desirable  edge-strength  to  amal- 
gams ;  and  furthermore,  that,  like  any  "  balancing  power,"  its 
great  usefulness  is  developed  in  exact  ratio  with  the  accurate 
meeting  of  requirements  on  the  part  of  the  other  component 
metals. 

It  is  for  this  reason  that  I  have  given  it  as  an  "undetermined 
element."  I  am  of  the  opinion  that  the  best  proportionate 
quantity  of  gold  will  eventually  be  proven  to  be  from  five  to 
seven  per  cent.,  while  the  value  of  this  definite  proportion  will 
depend  entirely  upon  the  accurate  proportionment  of  every 
other  component.  It  will  require  many  years  to  arrive  at  any 
positive  conclusion  on  this  point;  but  upon  it,  as  it  seems  to 
me,  depends  in  considerable  degree  the  ultimate  production  of 
an  aesthetic  "  usual "  amalgam  for  filling  teeth. 

ANTIMONY.     Stibium.     Symbol,  SB.    Fuses  at  840°  F. 

This  metal  has  been,  and  is  even  yet,  used  in  a  few  of  the 
many  alloys  at  present  offered  to  the  profession  with  the  ster- 
eotyped assertions  as  to  their  "  superior  excellence."  The  only 
difference  between  them  and  the  general  alloy  consists  in  the 
addition  of  a  portion  —  sometimes  quite  large  —  of  antimony. 
It  is  conceded  that  the  one  property  of  "shrinkage"  is  con- 
trolled by  this  modification,  and  that  the  grain  of  plasticity  is 
iiner ;  but  our  experiments  resulted  only  in  duplicating  pur- 
chased alloys  which,  when  made  into  amalgams,  proved  so  ex- 
cessively dirty  in  mixing  and  in  working,  that,  for  this  reason 
alone,  all  further  efforts  with  this  metal  were  abandoned. 

Shrinkage  is  so  satisfactorily  under  control,  and  fine-grained 
plasticity  is  so  easily  obtained,  that,  as  the  working  of  the  best 
amalgams  is  yet  accompanied  with  undesirable  degree  of  "soil" 
to  the  hands,  any  ingredient  which  only  accomplished  the  two 
requirements  above  mentioned,  and  did  it  with  excessive  in- 
crease in  so  objectionable  a  direction,  seemed  to  us  unworthy 
of  much  consideration. 


54  PLASTICS    AND    PLASTIC    FILLING. 

Zixc.     Zincum.     Symbol,  Zx.     Fuses  at  773°  F. 

As  the  alloys  of  copper  and  tin  have  been  spoken  of  as  very 
curious  and  valuable,  so  may  the  alloys  of  zinc  and  copper  be 
spoken  of  as  eminently  "ancient  and  honorable";"  and  when 
to  these  must  be  added  the  quality  of  exceeding  usefulness,  we 
may  well  come  to  the  consideration  of  zinc  with  befitting  care 
and  deference.  Not  that  it  has  been,  as  yet,  proven  to  be  of 
such  lasting  value  in  dental  amalgam  alloy  as  to  reflect  credit 
upon  its  "made  record;"  but  that,  like  gold,  its  possibilities 
may  be  something  of  vast  importance. 

Added  to  the  usual  "  40  silver,  60  tin  "  alloys,  in  the  propor- 
tion of  from  1  to  1  \  parts  in  100,  it  seems  to  control  "  shrink- 
age "  perfectly.  So  decided  is  this,  that  fillings  made  of  such 
amalgam,  in  tubes  of  five  or  six  times  the  diameter  of  those 
usually  employed  in  the  "leakage  test"-  —  with  blue  or  purple 
ink  —  give  no  perceptible  indications  of  permeation  of  fluid. 

Added  to  such  alloys  as  Lawrence's,  Harclman's,  Pierce's, 
—  made  from  analysis  of  "  Standard," —  "  Standard,"  etc.,  in  the 
proportion  of  even  less  than  1  part  in  100,  the  same  result  is 
produced.  Besides  this,  it  seems  to  impart  an  additionally 
"buttery"  plasticity  to  the  amalgam,  which  gives  it  excep- 
tionally fine  working  quality,  and  also  to  add  to  the  already  sat- 
isfactory whiteness  of  the  filling,  and  to  its  maintenance  of  color. 

Altogether,  the  effects  which  seem  to  be  due  to  limited  ad- 
mixture of  zinc  are  expressed  to  each  other,  by  experimenters, 
in  using  the  somewhat  vague  but  comprehensive  word,  "pe- 
culiar." It  is  hard  to  say  just  what  this  means,  or  in  what  de- 
gree in  any  direction,  but  it  signifies  that  the  "  feel "  of  the 
"  make  "  is  different ;  that  the  "  amalgamating  "  is  different ; 
that  the  "  working  "  is  different ;  that  it  "  sets  "  differently,  and 
that  the  final  result  is  different;  and  that  it  is  satisfactorily  so. 
This  line  of  work  is  of  such  comparatively  recent  date  —  a  few 
years — as  yet  to  be  entirely  within  the  boundaries  of  "ex- 
perimental." It  seems  to  promise  well,  but  the  intimate  relations, 
as  well  as  the  distinct  differences,  which  exist  bet\s'een  zinc  and 
cadmium  should  be  remembered. 

CADMIUM.     Cadmium.     Symbol,  CD.     Fuses  at  442°  F. 

It  is  about  .thirty  years  since  cadmium  amalgam  alloy  was 
suggested  to  the  profession  by  Dr.  Thos.  W.  Evans,  of  Paris. 


METALS    USED    FOR    AMALGAM    ALLOYS.  55 

The  promises  of  this  alloy  were  certainly  very  alluring  It 
was  easily  amalgamated;  the  amalgam  was  readily  inserted;  it 
did  not  discolor ;  it  "  set "  with  surprising  celerity  ;  it  made  a 
sufficiently  resisting  filling.  What  wonder,  then,  that  the  gentle- 
man Avho  introduced  it  was  pleased  with  the  material?  His 
mention  of  it,  however,  was  very  soon  proven  to  be  not  in  ac- 
cordance with  the  slowly,  and  sometimes  painfully  contracted 
habits  of  deliberation,  watchfulness,  and  long-enduring  patience 
which  pertain  —  as  a  part  of  himself — to  the  old  experimenter, 
but  must  be  viewed  as  entitled  to  our  respect  and  gratitude 
from  the  generosity  of  his  outpouring  of  that  which  seemed  to 
him  so  very  valuable  an  adjunct  to  the  practice  of  his  profes- 
sional brethren. 

My  own  experiments  with  cadmium  amalgam  were  disastrous 
in  the  extreme.  Presuming  upon  the  high  authority  of  its 
recommendation.  I  received  it  with  the  cordiality  of  a  young 
enthusiast,  introduced  a  large  number  of  fillings, — nearly  two 
hundred, — and  was  delighted  with  it. 

My  satisfaction  was,  however,  very  short-lived,  for  only  three 
or  four  months  passed  before  sundry  indications  presented, 
which  aroused  my  suspicions  as  to  the  uniform  integrity  and 
durability  of  the  material, — these  were  an  occasional,  but  evi- 
dent crevicing  at  edges ;  a  gradual  softening  and  disintegration 
of  some  fillings;  and  the  yellowish  discoloration  sometimes 
apparent  in  adjoining  tooth -structure. 

Having  kept  my  usual  list  for  statistics,  under  the  head  of 
"  cadmium  work,"  I  immediately  sent  for  several  patients  to 
examine  as  to  how  things  were  progressing.  Strangely  enough, 
so  large  a  proportion  of  the  fillings  looked  well  and  seemed  to 
be  doing  good  service,  that  my  suspicions  were  quieted  until 
the  time  arrived  for  the  periodic  dental  examinations  which  I 
early  instituted,  and  endeavored  by  persuasion  and  by  argument 
to  enforce,  among  my  patients. 

Then  it  was  that  I  became  fully  impressed  with  the  utter 
worthlessness  of  the  specious  amalgam.  Quite  a  number  of  fill- 
ings were  found  completely  "demoralized,"  and,  what  was  far 
worse,  quantities  of  dentine  had  become  thoroughly  decalcified 
and  stained  to  a  bright  orange-yellow  color — sulphide  of  cad- 
mium. 


56  PLASTICS    AND    PLASTIC    FILLING. 

I  at  once  undertook  the  most  thorough  examination  possible, 
and  commenced  the  work  of  reparation  of  damages.  So  far  as 
the  removal  of  fillings  in  pulpless  teeth,  and  their  replacement 
by  those  of  less  pretending,  but  more  trustworthy  materials 
was  concerned,  all  was  well  enough ;  for,  in  that  work,  no 
other  suffered  nearly  so  much  as  I.  But  of  the  teeth  containing 
vital  pulps,  of  which  I  am  truly  thankful  there  were  compara- 
tively few,  the  most  became  "  devitalized."  There  was  but  a 
very  occasional  recollection  of  pain,  and  this  had  been  of  so  slight 
a  degree,  as  not  to  have  compelled  a  visit  for  relief  upon  the 
part  of  any  one ;  but  in  such  cases,  as  I  gradually  removed  the 
yellow  portions  of  tooth-bone  until  I  finally  entered  the  pulp 
cavities,  I  found  more  or  less  thoroughly  devitalized  pulps.  In 
some  instances,  where  thick  septa  of  dentine  existed  between 
the  bottoms  of  the  cavities  of  decay  and  the  pulp  cavities,  the 
pulps  were  still  living ;  in  these  I  carefully  excavated  until  I 
had  removed  all  yellow  tissue,  saturated  the  remaining  dentine 
with  creosote,  as  was  then  the  practice,  and  refilled. 

Some,  even  of  these  pulps,  have  since  died  under  the  later 
fillings ;  the  putrescent  pulps  have  given  rise  to  peridental  irri- 
tation, and  the  fillings  have  either  been  removed  or  the  teeth 
have  been  tapped  and  treated.  Others,  again,  have  lived  and 
are  yet  living ;  but  even  these,  as  I  occasionally  see  them,  act  as 
reminders  of  my  woful  experience  with  cadmium  amalgam. 

But  cadmium  is  yet  a  component  of  a  few  of  the  present 
amalgam  alloys.  It  is  introduced  in  some  alloys,  in  very  small 
proportions,  from  one  to  three  per  cent.,  by  those  whose  expe- 
rience seems  to  dictate  to  them  the  propriety  and  the  advantage 
of  so  doing.  It  is  an  open  question  as  to  the  advisability  of 
even  this  slight  admixture,  but  for  such  alloys  as  have  this 
metal  incorporated  in  large  proportions,  and  even  such  exist, 
unblushingly  advertised  upon  the  pages  of  our  dental  publica- 
tions, I  have  but  one  opinion,  and  that  is,  that  they  should  be 
denounced  with  the  utmost  severity. 

As  I  have  said,  the  question  of  the  absolute  expunging  of 
cadmium  from  the  list  of  metals  permissible  in  amalgam  al- 
loys, or  of  its  retention  as  one  which,  in  very  limited  quantity, 
may  be  possessed  of  real  value,  is  yet  an  open  one.  So  far  as 
I  know,  there  are  no  positive  grounds  for  its  retention;  there 


METALS     USED    FOR    AMALGAM     ALLOYS.  57 

are  no  reasonable  deductions  which  point  to  it  as  of  any  value. 
I  do  not  know  of  any  essentials  to  a  good  alloy,  which  are  posi- 
tively given  by  cadmium,  unless  in  detrimental  quantities,  that 
are  not  attainable  by  means  which  are  not  questionable  ;  and  as 
I  cannot  but  fully  appreciate  the  probable  impossibility,  on  my 
part,  of  any  further  extended  experimentation,  such  as  I  have 
prosecuted  and  enjoyed  during  the  past  twenty-five  years,  I 
desire  to  caution  the  workers  of  the  present  day  as  to  the  need 
for  care  in  their  endeavors  for  the  "positive  placing"  of  cad- 
mium. 

While  I  could  not  do  other  than  concur  with  the  advisabil- 
ity of  careful,  thoughtful,  observant,  and,  above  all,  patient  cad- 
mium experiments,  I  nevertheless  feel  that  I  should  be  dere- 
lict if  I  did  not  give  it  as  an  opinion,  that,  though  cadmium  is 
a  most  enticing  metal,  it  is  also  a  most  dangerous  one. 

Those  forewarned,  surely  should  be  forearmed. 

PLATINUM.  Platinum.  Symbol,  PT.  Fuses,  alone,  only  be- 
fore the  oxy-hydrogen  blowpipe,  or  in  a  very  powerful  blast 
furnace. 

Although  this  metal  has  been  so  generally  thought  to  be  an 
important  one  in  amalgam  alloys,  and  although  its  value  has 
been  so  positively  stated  and  so  tacitly  acknowledged  as  to 
have  made  its  name  alone,  without  any  known  quantities,  or 
even  actual  presence,  of  sufficient  power  to  bestow  position  of 
eminence  upon  material  to  which  it  is  given,  I  have  nevertheless 
placed  it  last  upon  the  list  from  the  fact  that,  for  years,  it  has 
passed  from  the  notice  of  our  "New  Departure  Corps,"  and  has 
been,  by  us,  just  as  thoroughly  ignored  as  it  has  been,  in  pub- 
lic, ostentatiously  paraded. 

In  the  proceedings  of  the  "  New  York  Odontological,"  Dec., 
187-i,  page  52,  in  Dr.  E.  A.  Bogues'  paper  on  "  The  physical 
properties,  etc.,  of  dental  amalgams,"  the  following  is  given : 

"Fletcher's  Platinum  and  Gold  alloy,  marked  VIII.,  and 
yielding  upon  assay  these  two  different  results : 

Gold          .  .  3.60  Gold          .        .      5.10 

Platinum  .  .  3.30  Silver         .        .    39.50 

Silver         .  .  37.63  Tin    .        .        .    55.40 

Tin    .        .  .  55.47  Platinum,  none" 

The  information  that  a  "platinum  and  gold  alloy"  had  as 


58  PLASTICS    AND     PLASTIC    FILLING. 

i 

one  of  its  components  " platinum  none"  is  certainly  amusing ; 
but  that  "  dentistry  "  should  have  accepted  and  used  such  ma- 
terial because  it  was  "platinum  and  gold  alloy,"  is  assuredly 
discreditable  in  the  extreme. 

And  yet  in  this  instance  ignorance  ivas  bliss,  and  perhaps  it 
is  true  that "  when  ignorance  is  bliss,  't  is  folly  to  be  wise !  "  for, 
of  the  two  alloys  analyzed,  that  with  the  "  platinum  none  "  is 
the  better  alloy !  Its  39.50  of  silver  and  its  5.10  of  gold  gives 
it  quicker  setting,  better  edge-strength,  better  color,  and  less 
shrinkage  than  pertains  to  its  rival  with  only  37.63  silver  and 
3.60  gold ;  while  in  each  the  more  than  55  of  tin  does  all 
it  can  in  the  way,  of  decreasing  "  setting,"  permitting  "  bulg- 
ing," and  consequent  "crevicing"  and  diminishing  "edge- 
strength  ; "  surely  these  things  are  difficult  to  regulate,  even 
with  "judgment." 

The  conflicting  opinions  regarding  platinum  are  quite  equal 
in  antagonism  to  those  which  have  been  quoted  concerning 
gold. 

In  "New  York  Odontological,"  Dec.,  1874,  page  20,  Dr.  Cutler 
says:  "Filings  of  platinum  and  mercury  rubbed  together  .  .  . 
do  not  amalgamate  readily.  .  .  .  There  appears  to  be  no  affin- 
ity between  the  two."  "I  combined  platinum  with  silver  and 
tin  in  small  proportion,  and  found  that  just  in  proportion  to  the 
amount  of  platinum  was  the  amalgamation  retarded."  "  The 
next  experiment  was  with  platinum  and  gold,  one  equivalent 
of  platinum  and  two  of  gold ;  .  .  .  after  the  lapse  of  two 
weeks  it  was  not  firm,  ...  in  fact,  it  did  not  harden  to  any 
extent."  The  next  experiment  was  with  one  part  platinum, 
two  parts  gold,  and  three  parts  ordinary  allo}-.  "  The  mass  was 
grayish- white,  rather  dirty  in  appearance,  and  did  not  lecome 
hard  and  firm^  The  next  experiment  was  with  one  part  of 
platinum,  one  part  of  gold,  two  parts  of  silver,  and  two  parts 
of  tin.  After  twenty-four  hours  the  lump  was  "  white  and  pure, 
but  not  hard  enough  for  durable  work  ;  "  "  in  twenty-four  hours 
longer — in  forty-eight  hours — the  mass  had  become  quite  as 
firm  as  ordinary  amalgam."  This  was  a  mixture  of  platinum, 
gold,  silver,  and  tin — the  combination  which,  has  been  stated  as 
alone  utilizing  platinum. 

These  experiments  were  not  alone  made  with  "  alloys,"  but 


METALS    USED    FOR    AMALGAM    ALLOYS.  59 

were  a  "  line  of  work  "  in  what  we  call  u  mechanical  mixes  " — 
done  evidently  with  the  idea  that  such  mixing  was  equivalent 
to  alloying.  This  is  by  no  means  the  case,  but  the  work  is 
interesting  as  showing  the  effect  of  platinum  when  thus 
"mixed." 

Mr.  Fletcher  says — so  states  Prof.  Hitchcock — that  "  the 
amalgam  called  platinum -amalgam  is  composed  of  the  ordi- 
nary silver  and  tin  alloy  with  ten  per  cent,  fine  gold,  to  which 
sufficient  platinum  is  added  to  cause  it  to  set  quickly" 

The  quantity  required  to  produce  this  effect  is  not  given  ;  but 
it  may  be  well  to  recall  the  fact  that  without  the  platinum  the 
formula  is  practically  the  same  as  quoted  from  the  University 
of  Pennsylvania  Professor  of  Metallurgy,  Avhich,  minus  plati- 
num, he  said,  "  hardened  well  in  a  few  minutes." 

Prof.  Hitchcock  evidently  accepted  the  theory  of  the  quick- 
setting  control  of  platinum,  for  he  says  of  palladium,  "  When 
added  to  a  gold,  silver,  and  tin  amalgam,  it  hastens  the  setting 
about  the  same  as  platinum  does." 

When  we  read  from  Dr.  Cutler  that  the  "mechanical  mix" 
of  "  filings  and  mercury  do  not  amalgamate  readily  ;  "  "  do  not 
form  a  metallic  mass  at  all,  but  remain  in  the  form  of  a  dark 
powder ; "  and  that  "  there  appears  to  be  no  affinity  between 
the  two,"  and  when  we  read  from  the  University  Metallurgist 
that  "  a  very  smooth  and  plastic  amalgam  may,  however,  be 
formed  by  rubbing  some  finely  divided  platinum,  such  as  is  ob- 
tained by  precipitation,  with  mercury,  in  a  heated  mortar;" 
biit  that  "  an  amalgam  composed  of  platinum  and  mercury  does 
not  harden  well,"  and  that  in  an  alloy  of  tin,  silver,  and  plat- 
inum the  properties  were  "greatly  impaired  by  the  addition 
of  platinum  ; "  and  that  in  an  alloy  of  tin  and  platinum  "  the 
property  of  setting  was  almost  entirely  lost,"  and  when  all  ex- 
perimenters agree  that  palladium  amalgam  "  sets  "  with  such 
rapidity  that  unless  it  is  made  very  soft  it  cannot  be  properly 
inserted  as  a  filling,  it  seerns  doubtful  as  to  its  hastening  setting 
"about  the  same  as  platinum." 

But,  again,  while  it  has  been  usually  accepted  that,  in  some 
way,  platinum  is  a  very  advantageous  adjunct  in  an  amalgam, 
and  while  to  it  has  been  ascribed  the  power  of  preventing  dis- 
coloration alike  of  fillings  and  of  teeth  ;  the  increasing  of  plas- 


60  PLASTICS     AND    PLASTIC    FILLING. 

ticity ;  the  promotion  of  setting,  and  the  production  of  a  gen- 
erally excellent  ( ! )  filling  material,  it  has  been  taught  by  a  few 
that  "  the  real  value  of  platinum "  pertains  only  to  its  combi- 
nation with  tin,  silver,  and  (/old. 

Its  "  real  value  "  in  this  connection  is  stated  to  be  the  giving 
to  such  alloys  the  properties  of  "almost  instantly  setting"  and 
of  "greater  hardness." 

Even  granting  this  to  be  true,  the  "real  value"  of  this  metal 
seems  to  be  of  very  little,  if  indeed  it  is  of  any,  moment ;  for 
if,  as  we  know,  alloys  can  be  made  without  it,  composed  only 
of  silver,  tin,  and  gold  which  will  "  set "  with  even  more  than 
desirable  rapidity,  and  if,  as  I  have  stated,  the  softest  of  all  the 
amalgams  are  needlessly  hard,  and  the  harder  ones  would  be 
very  much  improved  if  they  could,  without  loss  of  other  valu- 
able quality,  be  made  softer,  then  the  "real  value"  of  platinum 
becomes  so  questionable  as  to  render  it  more  than  probable  that 
it  may  be  positively  detrimental. 

But  the  line  of  work  done  by  our  "corps"  does  not  corrob- 
orate either  assertion  concerning  much  control  of  discoloration ; 
much  control  of  "plasticity;"  much  control  of  "setting,"  or 
much  induction  of  "  hardness ; "  and  for  amalgam,  so  far  as 
"general  excellence"-— vague  and  unscientific  as  is  the  term  — 
is  concerned,  I  believe  that  one  part  of  zinc  is  worth  a  dozen 
times  more  than  a  dozen  parts,  or  any  other  number  of  parts, 
of  platinum.  • 

So  far  as  is  proven,  the  value  of  platinum  seems  to  be  just 
equal  with  that  of  tin.  Every  alloy  which  we  made  or  experi- 
mented with,  that  had,  in  place  of  certain  proportions  of  plat- 
inum, the  same  equivalents  of  tin,  set  the  same;  shrank  the 
same ;  gave  the  same  color-test ;  had  the  same  edge-strength ; 
and,  with  the  exception  of  being,  perhaps,  a  little  less  plastic 
and  a  little  less  tough,  worked  the  same;  and,  so  far  as  could  be 
positively  demonstrated,  were  practically  the  same. 

My  conclusion  is,  therefore,  that  except  in  name  (!)  the  metal 
platinum  is  valueless  as  a  component  of  amalgam  alloys  for  fill- 
ing teeth. 


THE    MAKING    OF    AMALGAM     ALLOYS.  61 

ARTICLE   VI. 
THE  MAKING   OF  AMALGAM  ALLOTS. 

THE  making  of  alloys  for  amalgam  is  a  branch  of  dental 
manufacture  the  importance  of  which  is  but  little  realized. 
I  took  occasion  to  direct  attention  to  the  large  proportions 
which  this  had  assumed,  when  I  read  my  paper  upon  "Plastic 
Filling  as  a  Power  in  Dentistry  "  at  the  American  Dental  As- 
sociation, August,  1878. 

NOTE. — This  paper  may  be  found  in  the  "  Dental  Cosmos"  for  September,  1878, 
page  474.  It  was  not  published  in  the  "  Transactions  "  of  the  Association.  The 
reason  for  non-publication  is  given  in  the  following  letter  from  the  chairman  of 
the  Publication  Committee. 

174  STATE  STREET,  CHICAGO,  April  5, 1S79. 
DR.  J.  FOSTER  FIAGG,  Philadelphia. 

Dear  Sir.  —  In  explanation  of  the  fact  that  the  paper  read  by  you  at  the  last 
meeting  of  the  American  Dental  Association  does  not  appear  in  the  "  Transac- 
tions," I  am  instructed  by  the  Publication  Committee  to  say  that  it  was  after 
careful  consideration  that  they  unanimously  decided  not  to  publish  it. 

In  the  Constitution  are  the  following  instructions  to  the  Publication  Commit- 
tee :  "  They  shall  superintend  the  publication  and  distribution  of  such  portion 
of  the  Transactions  as  the  Association  may  direct,  or  the  Committee  judge  to  be 
of  sufficient  value."  The  Committee  felt  compelled,  under  the  latter  clause  of 
these  instructions,  to  exclude  this  paper,  it  being  mainly  a  statement  of  the  claim 
of  the  writer,  of  his  greater  success  in  saving  teeth  —  by  means  of  a  system  of 
practice  KOT  described  —  over  that  of  other  practitioners. 

The  decision  of  the  Committee  was  not  actuated  by  any  personal  prejudice,  nor 
influenced  by  any  opposition  to  the  doctrine  advanced  in  this  paper,  but  was 
governed  solely  by  a  sense  of  duty. 

Believe  me  to  be,  in- behalf  of  the  Publication  Committee, 

Very  truly  yours. 

I  there  showed  that,  altlwu.ijh  amalgam  was  rather  decried 
as  a  filling  material;  that  it  was  only  used  in  exceptional  cases: 
that  its  employment  was  usually  spoken  of  as  derogatory  to 
"first-class"  ability,  and  that  the  almost  universal  testimony 
of  speakers  upon  it  was,  that  they  filled  with  it  but  "  very  in- 
frequently," it  nevertheless  required  the  united  manufacturing 
capability  of  more  than  twenty  makers  of  alloys  to  supply  the 
constantly  increasing  demand. 

Nearly  every  manufacturer  of  "  dental  supplies  ''  has,  through 
"  a  long  and  elaborate  series  of  experiments,"  arrived  at  the 


62  -PLASTICS    AND    PLASTIC    FILLING. 

same  formula,  and  each  is  "superior"  to  all  the  others!  By 
most  dealers  the  "  alloy"  is  advertised  as  an  "  amalgam,"  and  it 
is  thus  designated  by  those  who  purchase  and  use  it ;  the  dis- 
tinctive difference  between  the  two  being,  by  custom,  ignored. 

Occasionally,  some  speaker  has  given  his  formula  and  "  method 
of  making,"  and  in  the  aggregate  these  are  singularly  har- 
monious ;  from  first  to  last  the  silver  is  melted  first,  and  the  tin 
is  then  added  in  pieces,  or  each  is  molten  separately,  and  the 
two  melts  are  poured  together. 

As  platinum  and  gold  became  adopted  as  ingredients,  the 
process  continued  essentially  the  same.  Among  the  most  recent 
of  these  "  methods  "  is  that  given  by  the  Professor  of  Operative 
Dentistry,  University  of  Pennsylvania, —  "  Pennsylvania  Odonto- 
logical,"  March,  1879,  —  in  which,  after  stating  that  "much  de- 
pends upon  the  proper  alloying  of  the  metals,"  it  is  still  directed 
that  "  the  silver  should  be  melted  first,  and  when  at  a  boiling 
heat  the  platinum  should  be  added  in  very  small  particles,  either 
rolled  into  thin  ribbons  or  cut  into  minute  pieces.  Next,  the 
gold  should  be  added;  and,  lastly,  the  tin"  —  the  italics  are 
mine. 

Even  with  this  periodic  dissemination  of  instruction,  the 
making  of  alloy  seems  to  have  been  undertaken  but  by  few 
practitioners ;  no  education  in  regard  to  it  has  been  given  in 
most  of  the  colleges,  and  not  one  graduate  in  an  hundred  has 
any  definite  idea,  either  of  the  components,  the  proportions,  or 
the  properties,  of  the  materials  he  purchases  for  the  filling  of 
teeth,  other  than  as  given  him  upon  the  printed  envelope  or 
the  paper  of  "directions."  And  all  this,  notwithstanding  the 
time-honored  "  annual  announcements  "  from  "  chairs  of  Dental 
Metallurgy." 

Such  "  methods  "  are  not  held  in  high  esteem  by  the  "  New 
Departure  "  metal-workers,  for  their  method  is  so  very  different. 

For  the  making  of  alloy,  the  hessian,  or  sand  crucible,  is 
used.  In  this  is  first  fused  a  very  liberal  portion  of  borax, 
sufficient  in  amount  to  fill  the  crucible  at  least  one-third  full  of 
the  molten  salt.  This  is  intended  for  a  "flux."  Any  ordinary 
coke  or  coal-fire  is  all  that  is  required  for  the  "  melt ;  "  but  it 
is,  of  course,  more  systematically,  and  perhaps  more  readily, 
done  at  the  usual  dental  or  smelting  forge-fire. 


THE    MAKING    OF    AMALGAM    ALLOYS.,  63 

Having  perfectly  fused  the  borax,  in  it  the  tin  is  melted 
first,  requiring  but  a  low  temperature,  and,  after  it  is  melted, 
the  granulated  silver  is  added.  It  is  really  remarkable,  when 
the  high  fusing-point  of  silver  is  considered,  with  what  facility 
this  metal  is  taken  up  by  the  molten  tin.  These  two  metals 
are  thoroughly  stirred  together  with  an  iron  rod,  or  clay  pipe- 
stem  of  small  size,  and  suitable  length,  and  when  completely 
incorporated,  the  copper — small  pieces  of  wire — is  added.  This, 
like  the  silver,  notwithstanding  its  fusing-point  of  almost  2000°, 
is  soon  melted,  and  may  be  equally  homogeneously  mixed. 
Lastly,  the  gold  is  added,  melted,  and  all  is  thoroughly  stirred 
together  with  the  iron  rod  or  pipe-stem. 

When  perfectly  melted  and  mixed,  the  fused  mass  should  be 
quickly  poured  into  a  broad,  open,  flat,  shallow  matrix  made 
of  iron  or  soap-stone  ;  this  favors  prompt  cooling,  and  thus 
secures  the  greatest  uniformity  of  distribution  to  the  com- 
ponents. 

I  cannot  understand  how  any  reasonable  method  of  working 
metals,  even  silver  and  tin,  could  result  in  such  wholesale 
separation  of  the  components  of  an  alloy  as  that  described  by 
the  Professor  of  Metallurgy  at  the  April,  1880,  meeting  of  the 
New  York  Odontological.  I  can  believe  that  there  might  be 
approximation  to  the  almost  complete  separation  of  the  silver 
from  the  tin,  thus  leaving  one  end  of  the  ingot  nearly  all  silver, 
and  the  other  nearly  all  tin,  by  very  slow  cooling  and  very 
careful  work  for  the  definite  accomplishment  of  that  purpose;  but 
I  cannot  think  that  any  one,  in  the  least  degree  proficient  in 
"  making  melts,"  need  ever  fear  such  untoward  experience. 

On  the  contrary,  I  know  that  novices  in  the  working  of 
metals,  "first  course"  men,  are  in  the  habit  of  making  good 
samples  of  three  and  four  metal  alloys  with  but  comparatively 
little  practice. 

The  "  cutting  "  of  the  alloy  into  "  grains,"  "  filings,"  or  "  a 
kind  of  powder,"  as  it  is  variously  given  by  the  manufacturers, 
is  a  matter  of  grave  consideration  to  them,  as  it  is  a  trouble- 
some and  expensive  process,  just  in  proportion  to  the  goodness 
of  the  alloy.  Thus,  a  heavily  tin,  two  metal  alloy,  can  be  cast 
into  cylindrical  ingots,  and  "rasped  "  up  into  "grains,"  or  better 
yet  "  turned  "  up  into  "  shavings,"  with  rapidity  and  cheapness; 


64:  PLASTICS    AND    PLASTIC    FILLING. 

while  with  a  fine,  heavily  silvered,  four  metal  alloy,  the  work 
is  very  different,  and  is  both  laborious  and  much  more  ex- 
pensive; but  for  individual  need  it  is  only  necessary  that  the 
file  be  used. 

Here  again  the  quality  of  an  alloy  is  quite  accurately  tested ; 
for  while  the  coarse  files  known  as  "  vulcanite  files  "  are  best 
for  cutting  all  "  low  grade  "  or  "  ordinary  "  alloys,  they  are  not 
nearly  as  good  as  finer  files  for  cutting  "  high  grade  "  alloys. 

It  is  one  of  the  "  tests  "  for  a  good  alloy,  that  it  shall  not, 
in  cutting,  "  clog  "  a  fine  file. 

After  the  alloy  is  "filed  up,"  the  filings  should  be  passed 
through  a  fine  wire  sieve ;  this  removes  all  coarse  pieces,  bits 
of  leather  from,  the  wire  file-brush,  and  other  undesirable  im- 
purities Avhich  may  become  mixed  with  them  during  the  filing. 
After  this  the  filings  should  have  a  magnet  passed  through  them 
until  no  iron  filings  adhere  to  it ;  they  should  then  be  spread 
out  over  a  broad  surface,  and  carefully  blown,  either  by  the 
breath  or  small  bellows,  to  remove  any  dust ;  this  should  be 
done  gently,  as  the  finest  of  the  filings  are  light,  and  easily 
blown  away,  while  they  are  the  best  of  all  the  cut  alloy. 

The  filings  are  now  prepared  for  use,  but  they  are,  most  de- 
cidedly, not  ready  for  use. 

Although  manufacturers  have  not  hesitated  to  cut  up  large 
quantities  of  alloy,  and  keep  it  "  in  stock,"  without  fear  of  de- 
terioration, it  has  nevertheless  been  thought  by  them,  and  by 
the  profession  generally,  that  such  keeping  was  detrimental, 
and  from  this  belief  some  practitioners  have  filed  up  or  turned 
up  but  small  portions  of  their  ingots  at  a  time,  in  order  that 
their  material  might  always  be  ':  fresh,"  as  it  has  been  termed. 
Among  all  the  many  errors  which  have  obtained  in  connection 
with  alloys  and  with  amalgam,  there  is  probably  no  other  more 
decided  than  this.  There  is  no  alloy  made  that  does  not  work 
better  and  make  better  results  after  it  has  been  cut  lor  several 
weeks  than  can  possibly  be  the  case  where  it  is  "fresh,"  and  in 
this  particular,  as  in  every  other,  the  distinctions  are  so  marked 
between  "  ordinary"  and  "  high-grade  "  alloys,  that  an  "  expert  " 
can  decide  in  a  fe\v  minutes,  simply  by  mixing,  not  only  the 
quality  of  any  given  sample  of  alloy,  but,  approximately,  hoio 
lon'j  it  has  been  cut. 


THE     MAKING     OF     AMALGAM     ALLOYS.  65 

An  alloy  must  be  poor  that  will  mix  with  a  small,  relative 
proportion  of  mercury  and  work  satisfactorily  when  freshly 
cut.  And  inversely  I  can  state  that  no  really  good  alloy,  such  an 
one  as  will,  when  properly  "  aged,"  rank  well  as  amalgam  under 
the  "setting,"  "shrinkage,"  "edge-strength,"  and  "color"  tests, 
is  fit  to  work  unless  it  has  been  cut  at  least  two  months.  In 
my  own  practice,  I  never  use  any  alloy  that  has  not  been  cut 
for  three  or  four  months,  and  T  prefer  them  even  very  much 
older  than  that;  alloys  that  are  "dull  of  response,"  that  is, 
which  apparently  work  well  amalgamated  when  freshly  cut, 
shrink  notably,  set  slowly,  bulge  markedly,  and  have  little  or 
no  edge-strength. 

During  a  line  of  work  upon  the  mixing  of  various  fresh-cut 
alloys,  it  was  found  that,  by  placing  them  in  a  revolving  glass 
•cylinder,  and  maintaining  revolution  for  several  hours,  two 
simultaneous  effects  were  produced.  Not  only  were  the  alloys 
thoroughly  mixed,  but  a  result  analogous  to  that  which  is  given 
by  "  time."  became  apparent.  The  working  quality  was  much 
improved,  and  for  this  reason  the  double  name  of  ''  mixer  "  and 
"ager"  was  given  to  the  instrument  which  is  here  illustrated. 

Qualitative  Testing  of  Amalgam  Alloys. — The  following 
brief  directions,  for  which  I  am  indebted  to  Messrs.  Eckfeldt 
and  Du  Bois,  may  be  found  useful  and  interesting  to  those  who 
desire  a  general  idea  of  the  method  of  making  some  simple 
qualitative  tests  of  amalgam  alloys. 

Dissolve  from  ten  to  twenty  grains  of  the  alloy  in  a  small 
quantity  of  nitric  acid,  say  half  an  ounce,  by  the  application  of 
gentle  heat. 

The  appearance  of  the  solution  gives  the  first  clue  to  its  com- 
position ;  the  tin,  being  undissolved,  shows  itself  in  the  form 
of  a  white  precipitate. 

Should  gold  be  present,  the  tin  will  be  colored  from  a  light 
to  a  deep  purple  according  to  the  proportions;  suffice  it  to  sm- 
th. at  less  than  one-half  of  one  per  cent,  will  make  quite  a  de- 
cided purple. 

The  presence  of  platinum,  with  or  without  the  gold,  gives  the 
tin  a  dirty,  blackish  color,  and  the  platinum  being  partly  dis- 
solved by  the  nitric  acid,  the  whole  solution  is,  likewise,  dis- 
colored. 


66  PLASTICS    AND    PLASTIC    FILLING. 

Copper,  in  quantity,  colors  the  solution  green  or  blue. 

These  are  the  first  general  appearances  which  determine  the 
presence  of  tin,  gold,  platinum,  and,  possibly,  copper. 

For  the  determination  of  the  remaining  metals  found  in  these 
alloys,  the  solution  should  first  be  evaporated  to  dry  ness  ;  then 
dilute  with  distilled  water  and  eliminate  the  oxide  of  tin  by 
filtering. 

The  silver  will  be  precipitated  as  a  chloride,  flocculent,  but 
densely  white,  by  treating  filtrate  with  very  dilute  hydro- 
chloric acid.  Eliminate  by  collecting  on  filter. 

Copper  will  show  itself  by  a  blue  color,  if  a  small  portion 
of  the  filtrate  be  now  tested  by  pouring  into  it  a  little  ammonia. 
Should  this  not  appear,  treat  the  filtrate  with  sulphuretted  hy- 
drogen. If  cadmium  be  present,  it  will  be  shown  by  a  bright 
yellow  precipitate.  If  the  color  be  not  bright  yellow,  but 
brownish,  it  indicates  that  some  silver  has  either  been  left  un- 
prccipitated  by  the  chlorine  or  has  passed  through  the  filter. 

Should  the  ammonia  test  decide  the  presence  of  copper,  treat 
filtrate  with  sulphuretted  hydrogen  as  before  directed,  and  a 
black  precipitate  of  sulphide  of  copper  will  result,  unless  modi- 
fied in  color  by  a  large  percentage  of  cadmium.  Collect  this 
copper,  or  mixed  precipitate,  on  a  filter  (preserving  the  filtrate)  ; 
if  copper  and  cadmium  both  be  present,  the  precipitate  must  be 
boiled  in  dilute  sulphuric  acid ;  this  dissolves  the  cadmium  and 
leaves  the  copper  to  be  collected  on  a  filter. 

Treat  this  last  filtrate  with  sulphuretted  hydrogen,  adding  a 
few  drops  of  ammonia  to  the  solution,  to  modify  hyper-acidity. 
The  bright  yellow  precipitate  will  be  the  sulphide  of  cadmium. 

Lastly,  boil  down  the  first  filtrate  from  copper,  or  mixed  pre- 
cipitate referred  to  above,  until  nearly  dry,  to  expel  the  sul- 
phuretted hydrogen  ;  then  add  a  little  pure  water  and  a  solution 
of  carbonate  of  soda  until  neutralized.  The  presence  of  zinc 
is  then  proved  by  the  white  carbonate  of  zinc  now  precipitated. 


TESTS     FOR    AMALGAM.  67 

ARTICLE   VII. 
TESTS  FOR  AMALGAM. 

THE  various  "tests"  for  amalgam  are  (1)  the  "quality"  test; 
(2)  the  "  shrinkage  "  test ;  (3)  the  "  setting  "  test ;  (4)  the 
"color"  test;  (5)  the  "edge-strength"  test;  (6)  the  "tooth-con- 
serving" test. 

First.  Quality  Test.  —  The  quality  of  an  amalgam  depends 
upon  the  quality  of  the  alloy  with  which  it  is  made,  the  quan- 
tity of  mercury  with  which  it  is  mixed,  and  the  method  by 
which  the  filings  are  incorporated  with  the  mercury.  The 
quality  of  the  mercury  has  no  appreciable  influence  upon  amal- 
gam ;  it  is  only  needed  that  it  be  pure,  that  is,  practically  free 
from  metallic  admixtures ;  thus,  the  mercury  as  sold  in  the  ten- 
pound  stone  bottles  is  perfectly  adapted  for  making  dental 
amalgam,  and  the  necessity  for  having  it  "  double  distilled  "  — 
a  quality  thought  to  be  something  finer  than  is  usually  sold  — 
is  merely  ideal.  /  "  double  distill "  by  pouring  from  my  ten- 
pound  bottle  of  "  battery  mercury  "  into  my  box- wood  mercury 
holder. 

Mercury  which  has  been  used  for  making  a  button  of  amal- 
gam, and  has  been  "  squeezed  out "  as  superfluous,  should  not 
be  returned  to  the  mercury  holder,  as  it  contains  an  indefinite 
amount  of  various  metals  in  unknown  quantities.  The  presence 
of  these  metals,  held  loosely  for  a  length  of  time  in  the  mer- 
cury, not  only  prevents  the  making  of  a  "  known  "  amalgam  by 
its  use,  but  likewise  so  affects  the  mercury  as  to  render  it  a  less 
powerful  melter  of  the  other  metals,  thereby  requiring  a  larger 
relative  proportion  of  mercury  than  is  desirable  in  the  making 
of  any  given  amalgam. 

Testing  quality  is,  however,  governed  by  different  considera- 
tions from  making  amalgam,  though  the  need  for  pure  com- 
mercial-mercury is  equal  in  both  directions.  And  thus  it 
is,  that  while  each  kind  of  alloy  requires  a  definite  relative 
amount  of  mercury  and  especial  methods  of  mixing  for  the 
attainment  of  the  best  filling  possible  to  be  made  from  it,  all 
alloys  require  that  the  same  relative  proportion  of  mercury 


68  PLASTICS    AND    PLASTIC    FILLING. 

shall  be  used  in  the  making  of  "  test-buttons"  that  shall  decide 
"  quality." 

The  .reason  for  this  is,  that  it  is  essential  that  one  definite 
proportion  of  metal  be  known  ;  and,  as  the  mercury  is  the  only 
metal  to  be  added,  of  this  must  be  made  the  definite  addition. 

For  this  purpose,  then,  equal  parts  of  mercury  and  alloy 
should  be  taken, —  these  proportions  have  been  chosen  for  the 
reasons  that  they  are  most  easily  weighed, —  the  mercury  being 
placed  in  one  scale  and  the  filings  in  the  other,  and  these  ac- 
curately balanced ;  and  that  no  alloy  in  present  general  use 
requires  such  an  amount  of  mercury  for  the  making  of  an 
amalgam  fit  for  filling  purposes. 

Filling  purposes  and  testing  purposes  are  different ;  in  that 
for  filling,  rapidity  of  accomplishment  of  purpose  —  within  the 
bounds  of  obtainance  of  excellent  result  —  is  desirable  ;  while 
for  testing,  reasonably  slow  progress  better  demonstrates  rela- 
tivity of  consecutive  showings. 

Having  weighed  the  portions  of  mercury  and  alloy  to  be 
tested,  the  method  of  mixing  is  practically  immaterial.  The 
mix  may  be  made  in  the  palm  of  the  hand ;  it  may  be  a 
"shaken-mix," — as  suggested  by  Mr.  Fletcher, —  pressed  into 
form  by  his  mould ;  or  it  may  be  the  usual  "  mortar-mix," 
with  the  subsequent  palm-kneading. .  In  no  case,  however, 
should  any  of  the  mercury  be  removed  from  the  mass.  Thus, 
if  the  mass  be  pressed  in  a  Fletcher  mould,  it  should  be  al- 
lowed to  retake  the  mercury  squeezed  out  in  the  packing. 

By  any  of  these  various  methods  of  mixing,  "buttons"  of 
different  degrees  of  plasticity  are  made  which  are  in  known 
accord  with  the  varying  composition  of  alloys. 

Buttons  made  from  alloys  of  tin  and  silver  —  largely  tin  — 
are  very  soft,  having  the  peculiar  plasticity. of  tin;  these  "set" 
slowly;  gain  edge-strength  with  the  utmost  deliberation;  never 
attain  an  acceptable  edge-strength ;  retain  for  a  long  time  —  an 
hour  or  more,  according  to  the  relative  quantity  of  tin  —  a  de- 
gree of  exterior  softness  which  permits  of  marking  by  rubbing 
gently  with  the  finger,  and  are  easily  crushed  or  broken  after 
several  hours  of  hardening. 

Those  made  from  alloys  of  silver  and  tin  —  largely  silver  — 
are  much  firmer  in  consistency ;  have  the  peculiar  crepitation, 


TESTS    FOR    AMALGAM.  69 

indicative  of  silver,  in  making;  "set"  much  less  deliberately; 
gain  edge-strength  more  satisfactorily;  attain  fair  edge-strength 
in  from  two  to  four  hours ;  and  lose  in  an  hour  that  exterior 
softness  which  permits  of  "  finger-marking." 

Those  from  alloys  of  tin,  silver,  and  copper  —  largely  tin  — 
have  the  peculiar  ';  feel "  given  to  alloy  by  copper.  This  may 
well  be  called  peculiar,  and  yet,  to  one  who  is  a  decided  "  ex- 
pert "  in  this  method  of  analyzing,  it  is  very  cognizable. 

NOTE.  —  Some  years  since,  Dr.  Weston  —  of  Weston's  alloy — was  calling  upon 
me  in  relation  to  these,  to  us,  very  interesting  matters,  when  a  sample  of  alloy, 
which  I  had  requested  a  friend  to  obtain,  was  handed  to  me.  I  opened  the 
package,  and  giving  Dr.  Weston  some  of  the  alloy,  requested  an  "  approximate 
analysis."  Rubbing  it  up  with  the  palm-mix  and  gently  manipulating  it  for  a 
few  minutes,  he  remarked,  "  It's  a  little  peculiar.  I  think  it  is  pretty  nearly 
equal  parts  of  tin  and  silver,  with  -er  a  little  -er  copper  in  it  —  say  about  four  or 
five  parts  in  a  hundred."  It  was  Lawrence's  alloy. 

Test  amalgams  of  these  alloys  "set"  less  slowly  than  those 
of  tin  and  silver  of  this  grade;  but  the  "setting"  due  to  cop- 
per is  "  grainy,"  not  firm,  and  is  accompanied  with  a  character- 
istic ichiteniny  of  the  mass.  They  remain  softish  for  quite  a 
time, —  nearly  an  hour, —  and  their  edge-strength  is  not  good. 
According  to  our  experiments,  these  begin  to  represent  "good 
alloys." 

Alloys  of  silver,  tin,  and  copper  —  largely  silver  —  are  in- 
creasedly  satisfactory  in  all  directions:  they  set  with  increased 
promptness ;  they  harden  satisfactorily  and  with  firmness ;  they 
have  reasonable  whiteness  ;  they  have  desirable  edge-strength  ; 
in  an  hour  they  have  all  these  test  requisites  in  test  sufficiency. 

Alloys  of  tin,  silver,  and  gold  —  largely  tin  —  are  those  which 
first  give  apparently  "excellent"  testings:  they  work  with  a 
pleasant  plasticity ;  they  harden  reasonably  well  and  with 
reasonable  firmness;  their  edge-strength  seems  to  reach  "quite 
satisfactory  "  in  quality ;  if  they  are  cut  with  fineness,  in  the 
form  of  thin,  light,  shavings,  bulky  in  mass  but  diminishing 
most  notably  on  amalgamating,  the  mass  sets  more  promptly,: 
and  all  these  qualities  are  particularly  noticeable  to  those  who, 
as  a  rule,  have  been  habitually  working  the  tin  and  silver  — 
largely  tin  —  alloys.  : 

It  is  due  to  these  facts  that  testimonials,  honest  in  their  inno- 


70  PLASTICS    AND    PLASTIC    FILLING. 

cence,  are  found  attached  in  great  numbers  to  the  advertise 
ments  of  this  tin,  silver,  and  gold  class  of  alloys.  The  givers 
have  used  alloys  "  comparatively  infrequently ; "  they  have  used 
them  upon  the  recommendation  of  their  makers,  and  with  no 
knowledge  of  components  or  proportions.  They  have  learned 
to  recognize  certain  peculiarities  of  make,  set,  hardness,  and 
capability  of  finish,  as  characteristic  of  "  amalgam,"  and  the 
marked  differences,  which  even  a  little  gold  is  able  to  confer 
upon  even  the  stereotyped  alloys,  appear  to  them  as  "  something 
extraordinary." 

When  such  alloys  are  subjected  to  "  general  testing,"  their 
deficiencies  become  very  decided,  and  they  are  proven,  in  real- 
ity, to  be  but  little  better  than  their  tin  arid  silver  predecessors 
of  the  amalgam  "  middle  age." 

Buttons  made  from  alloys  of  silver,  tin,  and  gold  —  largely 
silver,  but  sufficiently  of  gold  —  are  the  beginning  of  something 
fine.  They  mix  with  combined  rigidity  and  plasticity ;  their 
crepitation  is  that  due  to  the  combination  of  silver  and  gold, 
4(  short,  sharp,  and  decisive,"  and  peculiarly  pleasing  to  the  initi- 
ated ;  their  setting  is  prompt,  firm,  and  dense ;  they  evince 
excellent  edge-strength ;  and  at  a  time  when  the  buttons  of 
amalgam  from  tin  and  silver  can  readily  be  scraped  away  with 
the  finger-nail,  the  buttons  of  silver,  tin,  and  gold  can  be  as 
readily  handsomely  burnished. 

I  have  had  the  pleasure,  frequently,  of  demonstrating  these 
things,  and  from  expressions  of  developing  convictions,  great 
satisfaction,  and  marked  degree  of  interest,  I  have  been  led 
to  conclude  that,  if  this  line  of  work  is  done  by  one  familiar 
with  it,  no  other  is  capable  of  so  thoroughly  impressing  the 
student  with  the  wonderful  difference  between  alloys,  the 
absolute  need  for  "  knowledge "  in  this  connection,  and  the 
perfect  facility  with  which,  by  its  possession,  one  can  separate 
the  "  tares  "  from  the  "  wheat." 

In  the  quality  testing  of  alloys  of  silver,  tin,  gold,  and  cop- 
per, or  of  those  of  tin,  silver,  gold,  and  zinc,  the  work  is  much 
increased  in  difficulty  and  delicacy.  To  do  this  with  any  ap- 
proximate to  accuracy,  it  is  necessary  that  one  shall  have  made 
hundreds  of  makes  of  known  different  alloys ;  and  even  then  it 
can  only  be  "  inferential."  But  with  this  experience,  a  general 


TESTS    FOR    AMALGAM.  71 

idea  can  be  formed  upon  which  can  be  predicated,  more  surely, 
the  fine  work  of  analyzing  such  materials,  and  the  finer  work, 
still,  of  suggesting  such  modifications  as  would  probably  be  im- 
proving. 

Here  is  a  field,  indeed,  for  the  thought,  energy,  and  discus- 
sions of  the  "coming  dentist," — afield  which,  though  it  has 
yielded  fine  results,  has  been  but  comparatively  superficially 
cultivated.  While  I  think  that  the  workers  of  "  The  New  De- 
parture Corps  "  have  done  dentistry  solid  service  in  the  labors 
which  they  have  accomplished,  I  yet  feel  that  each  member  of 
that  band  now,  more  fully  than  ever  before,  recognizes  that,  in 
the  aggregate,  the  task  performed  is,  to  the  task  yet  to  be  done, 
as  but  a  little  part. 

In  testing  the  quality  of  such  alloys  as  contain  cadmium,  the 
presence  of  this  metal  is  usually  indicated  very  promptly  upon 
amalgamation  ;  in  proportion  of  three  or  four  per  cent,  the 
"  cadmium  feel  " —  a  sort  of  slippery  stick  or  greasy  catch  —  is 
just  sufficiently  apparent  to  excite  suspicion;  it  is  also  dirty 
in  its  working,  and  leaves  much  soil  closely  adherent  to  the 
fingers  ;  it  also  causes  "  cadmium  setting  "  in  sufficient  degree 
to  be  noticeable.  This  setting  is  rapid  but  devoid  of  strength. 
Antimony  gives  some  of  these  peculiarities,  but  cadmium  is 
detected  with  reasonable  facility  after  it  has  been  experienced 
a  few  times  in  testings. 

Zinc,  as  a  component  of  amalgam,  is  not  brought  into  special 
notice  by  the  "  quality  test,"  except  as  it  seems  to  cause  adhe- 
sion of  the  mass  to  the  pestle  during  making ;  this  is  so  marked 
in  alloys  containing  zinc  in  from  two  to  four  per  cent,  that  it  is 
well  worthy  of  note. 

Second.  Shrinkage  Test. —  I  believe  that  to  Mr.  John  Tomes 
first  occurred  the  idea  of  testing  the  bulk  integrity  of  amal- 
gam ;  his  work  upon  this  point  was  clone  about  twenty  years 
ago.  So  firmly  had  the  belief  in  "  expansion "  of  amalgam 
become  impressed  upon  the  dental  mind,  that,  notwithstanding 
the  conclusive  proof  given  by  Mr.  Tomes  in  favor  of  "  contrac- 
tion "  or  "  shrinkage,"  as  it  is  variously  designated,  as  shown 
by  the  whole  line  of  tin  and  silver  amalgams,  dentistry  con- 
tinued to  believe,  as  it  had  been  taught  before,  that  amalgam 
expanded  in  its  setting. 


72  PLASTICS    AND    PLASTIC    FILLING. 

Mr.  Fletcher,  of  Warrington,  England,  followed  in  this  line 
of  experiment  with  his  practical  "tube  tests."  Of  these  I 
have  done  an  immense  number.  The  advantage  of  the  "  tube 
test "  over  that  of  the  "  amalgam  micrometer  "  is  the  possibility 
of  doing  a  number  of  experiments  in  a  limited  time,  as  tube 
after  tube  can  be  packed  and  set  aside  for  results,  while  with 
the  micrometer  each  packing  has  to  remain  in  the  instrument 
until  the  result  is  obtained.  This  requires  from  several  days 
to  many  months  for  each  experiment;  but  while  the  tube  test 
is  practical,  reliable  micrometric  work  is  more  accurate,  and 
particularly  as  regards  relativity  of  contraction  or  expansion, 
and  is  therefore  essential  to  progressive  experimentation. 

NOTE. —  I  must  agree  with  the  experience  given  by  Dr.  Geo.  B.  Snow,  "  Odon- 
tological  Proceedings,"  Dec.,  187-1,  page  07,  in  that  I  have  never  been  able  to 
obtain  the  peculiar  mirror-like  appearance  which  I  have  seen  in  some  specimen 
tubes  sent  to  this  country  by  Mr.  Fletcher,  even  though  I  have  repeatedly  tube- 
packed  amalgam  made  from  his  alloys  mixed  both  dry  —  powdery  —  and  with 
sufficient  mercury  for  plastic  working. 

For  the  introduction  of  the  "  index  "  amalgam  micrometer,  I 
believe  we  are  indebted  to  Prof.  Hitchcock ;  but  the  work  done 
by  him  with  his  instrument,  as  presented  at  the  New  York 
meeting,  while  so  very  questionable,  upon  the  slightest  exami- 
nation, as  to  make  it  seem  incredible  that  it  should  have  been 
presented  in  good  faith  by  any  one  to  any  scientific  body,  is,  at 
the  same  time,  in  a  certain  sense,  instructive,  and  may,  by. 
giving  it  only  a  passing  notice,  prove  of  value  as  a  warning 
to  other  dental  organizations,  before  which  such  papers  might 
be  read  in  future. 

The  whole  series  of  experiments  are  so  loosely  done;  so 
completely  inharmonious  in  their  relation  the  one  to  the 
other ;  so  impossible  of  production,  if  done  with  an  instrument 
of  the  least  pretensions  to  accuracy,  in  the  hands  of  an  experi- 
menter of  even  limited  experience,  that  no  value  whatever,  as 
bases  for  amalgam  alloy  work,  can  attach  to  them. 

I  have  already  stated  that  the  analyses  are  unreliable  so  far 
as  regards  practicality,  and  have  shown  that  the  marketed  alloys 
of  the  same  names  are  not  composed  of  the  metals  or  propor- 
tions there  given  —  with  one  exception ;  but  I  shall  have  to 
now  suppose  that  the  analyses  were  correctly  made  from 


TESTS    FOR    AMALGAM.  73 

samples  furnished  by  the  various  manufacturers  —  a  thing 
which  I  am  sorry  to  have  to  do  —  in  order  to  prove  the  want 
of  accord  between  the  results  as  "  shrinkage  measurements" 

Alloys  made  of  the  metals  given,  in  the  proportions  given, 
do  not  relatively  "shrink"  as  stated,  whether  mixed  "dry," 
"  medium,"  or  "  full  ;  "  whether  "  washed  "  or  "  not  washed." 
Two  or  three  examples  will  show  this  : 

"Arlington's  "  Silver     .     .  40    Expanding  component. 
Tin     ...  60    Contracting  component. 
"Shrank  .0045." 

"  Townsend's  Improved." 

Silver       .     .     .  39.00    Expanding  component. 
Gold   ....    5.31     Eminently  preventive  of  shrinkage. 
Tin      ....  55.69     Shrinking  component. 
"Shrank  .014."  (!) 

That  is,  an  alloy  with  44.31  parts  of  expanding  and  non- 
shrinking  components,  and  55.69  parts  of  shrinking  com- 
ponents, shrank  three  times  as  much  as  one  composed  of  only 
40  parts  of  expanding  components  and  60  parts  of  shrinking 
components  ! 

Again,  as  if  in  more  complete  derision  of  this  famous 
"shrinker,"  —  Townsend's  Improved  —  "Walker's,"  with  an 
analysis  which  places  it  for  shrinkage  in  exactly  the  same 
grade  of  alloys  with  "Arrington's," 

Silver      ....  34.89  1      39  parts  expanding  and  non-shrinking;  1 
Gold  .....     4.14)          neutral, 


"  Shrank  "  only  .002.  (!) 
But,  strangest  of  all,  "  Johnson  &  Lund,"  with  an  analysis  of 

Silver      ....  38.27  )  39  parts  expanding  and  non-contracting; 

Gold       .....  81  I  li  parts  neutral, 

Platinum    .               1.34  )  _nl 

Tin    .....  59.581  ^  Parts  contractmg, 

Shrank  .001+. 

Thus,  this  alloy,  which  expends  only  16  cents  —  per  ounce 
of  alloy  —  for  gold  to  control  the  shrinkage  of  its  60  per  cent. 
of  tin  to  the  minimum  (.001-f),  handsomely  exceeds  "Walk- 


74  PLASTICS     AND    PLASTIC    FILLING. 

er's  "  control  of  his  60  per  cent,  of  tin,  at  an  expenditure  of  94 
cents  —  per  ounce  —  for  gold;  and  leaves  "  Townsend's  Im- 
proved," with  its  determined  control  of  only  55.69  per  cent, 
of  tin,  by  an  expenditure  of  $1.06  —  per  ounce  —  for  gold,  so 
far  in  the  rear  that  the  difference  can  only  be  viewed  in  con- 
trast. 

It  seems  to  me  that  further  comment  on  such  work  is  need- 
less. And  yet  the  idea  of  the  index  micrometer  is,  to  a  cer- 
tain extent,  a  good  one. 

The  "index"  instrument  which  I  use  for  "shrinkage"  meas- 
urements was  made  by  Mr.  Henry  Coy, —  the  well  known  HC, 
—  whose  monogram,  upon  his  excellent  make  of  goods,  has  for 
so  many  years  duplicated  that  of  S.  S.  W.,  and  was  presented  as 
a  contribution  from  him  to  the  armamentarium  of  experimen- 
tal alloy  work.  It  was  made  from  the  copy  of  Prof.  Hitch- 
cock's instrument  used  by  Dr.  Bogue,  and  loaned  me  by  him. 

By  suggestions  of  Mr.  Coy  very  decided  improvements  upon 
the  original  micrometer  were  made ;  the  great  desideratum  of 
accuracy  of  packing  is  much  more  perfectly  accomplished;  the 
shape  of  the  circular  end  of  the  short  arm  of  the  "  pointer  " 
was  materially  altered,  as  the  circle  of  the  original  pointer  fa- 
vored largely  the  heavy  shrinkers  and  condemned  unsparingly 
the  light  shrinkers;  a  sliding  matrix-slot  was  so  arranged  that 
the  ingot  could  be  easily  and  safely  removed  at  conclusion  of 
experiment,  that  other  experiments  pertaining  to  density  and 
strength  of  alloy  might  be  performed ;  and  in  this  improved 
condition  the  instrument  is  well  represented  in  the  annexed 
illustration. 

By  this  instrument,  it  is  shown  that  there  is  relativity  be- 
tween composition  and  shrinkage ;  the  heavily  tin  alloys  make 
amalgams  which  shrink  most  notably.  If  to  these  alloys  gold 
or  copper  is  added,  the  shrinkage  is  lessened  in  approximately 
just  relation  with  the  amount  of  non-shrinkers  introduced! 

But  it  is  to  the  measurement  of  the  amalgams  made  from 
the  heavily  silver,  tin,  and  copper ;  and  silver,  tin,  gold,  and 
copper  alloys  that  we  are  now  most  attracted;  for  "shrinkage" 
in  connection  with  these  is  reduced  to  "  team  rifle-practice." 

For  this  purpose,  I  now  use  the  two-inch  matrix  —  micro- 
metric  —  and  direct  microscopic  measurement. 


TESTS    FOR    AMALGAM.  75 

To  one  of  Queen's  Household  Microscopes  the  following 
alterations  were  suggested  by,  and  made,  under  the  direction 
of  Mr.  E.  Pennock,  to  adapt  it  to  this  service. 

The  stage  is  altered  by  elevating  the  spring-clips  to  take 
the  plate  containing  the  matrix  with  the  amalgam  ingot  to  be 
tested. 

A  oiie-half-inch  object-glass  of  wide  aperture,  which  is  bet- 
ter suited  for  examining  opaque  objects,  is  adapted  to  the  in- 
strument. 

A  Jackson  eye-piece  micrometer  is  fitted  to  the  eye-piece, 
and  a  stage  micrometer,  ruled  to  y^0ths  and  j-^gths  of  an  inch, 
is  furnished  for  obtaining  the  value  of  the  divisions  of  the  eye- 
piece micrometer.  The  latter  is  adjustable  by  a  screw,  for  the 
purpose  of  bringing  one  of  the  lines  of  the  micrometer  to  coin- 
cide accurately  with  the  margin  of  the  space  to  be  measured. 
This  is,  of  course,  between  the  free  end  of  the  amalgam  ingot 
and  the  sliding  matrix -slot. 

By  this  instrument  and  arrangement  fine  work  can  not  only 
be  done  in  its  aggregate,  but  the  gradation  of  shrinkage,  until 
completion,  can  be  watched  and  noted  with  reliable  accuracy. 

Third.  Setting  Test. — For  this  test,  it  is  of  importance  that 
the  exact  amount  of  mercury  best  adapted  to  the  proper  work- 
ing of  each  given  alloy  be  ascertained.  Each  sample  is  then 
mixed  and  worked  just  as  it  would  be  in  the  filling  of  a  tooth. 
The  object  is  to  obtain  the  possibilities  of  each  amalgam ;  but 
in  my  present  amalgam  experiments  I  have  abandoned  the 
"  dry-mix  "  —  as  it  is  called  —  and  also  the  use  of  warm  instru- 
ments for  the  introduction  of  the  filling ;  but  any  expedient  is 
permissible  for  the  hastening  of  "  setting." 

The  greatest  difference  conceivable  exists  in  the  behavior 
of  different  amalgams  under  this  test;  for  with  some  —  notably 
those  made  from  the  silver,  tin,  and  gold  alloys  —  teeth  can  be 
"  built  up  "  in  such  wise  as  that  they  will  sustain  clasp-work  in 
from  thirty  minutes  to  an  hour;  while  with  amalgams  of  mer- 
cury, tin,  and  silver,  such  manipulation  can  hardly  be  per- 
formed as  will  permit,  first,  of  the  immediate  "  building  up," 
and,  second,  of  the  utilizing  for  clasps,  in  less  than  several 
hours,  if,  indeed,  in  less  than  a  day,  with  perfect  safety. 

In  mere  experimental  testing  for  "  setting,"  the  "  set "  is  re- 


76  PLASTICS    AND    PLASTIC    FILLING. 

garded  as  accomplished  when  the  filling  will  take,  without 
necessarily  retaining,  a  bright,  smooth  burnish. 

Fourth.  Color  Test. — By  universal  consent,  I  believe,  sul- 
phuretted hydrogen  water  is  used  for  this  test.  In  my  experi- 
ments I  use,  for  quick  results,  this  water  as  it  is  employed  in 
ordinary  metallurgic  work  —  full  strength;  but  it  is  much  bet- 
ter, and,  in  fact,  essential,  for  the  determination  of  gradation  of 
discoloration  of  amalgams,  that  the  tests  be  made  with  dilute 
sulphuretted  hydrogen  water,  1  part  to  2,  4,  or  6  parts  of  dis- 
tilled water. 

In  such  dilutions  the  gradual  discoloration  of  the  sample  is 
accurately  noted. 

Some  very  strong  sulphuretted  hydrogen  tests,  such  as  solu- 
tions of  sulphuret  of  potassium,  etc.,  have  been  suggested,  and 
have  been  represented  as  conclusive  provers  of  "  superiority " 
in  amalgams.  This  opinion  is  not  only  erroneous  in  theory,  but 
is  very  deceptive  in  fact.  So  far  from  being  a  test  of  superior- 
ity and  goodness,  a  powerful  sulphuretted  hydrogen  "color  test" 
is  one  of  the  best  tests  for  general  inferiority  and  badness.  Any 
amalgam  which  will  not  discolor  at  all  in  this  test  should  be 
viewed  with  much  suspicion,  and,  indeed,  it  may  be  regarded 
as  convicted  —  upon  prima  facie  evidence  —  of  some  serious 
deficiency.  The  presumption  is  that  the  amalgam  is  "  cadmi- 
umed;"  and  that  just  in  proportion  as  it  retains  good  color, 
so  is  it  loaded  with  this  tooth-destroying  metal. 

It  is  very  important  to  know  that  rather  inverse  to  the  good 
maintenance  of  color  is  the  real  value  of  amalgam. 

In  cases  where  cavities  can  be  nicely  "  lined  "  either  with 
good  varnish  or  good  oxy-chloride  of  zinc,  it  is  better  that  an 
amalgam  of  good  maintenance  of  color  be  used;  but  if  the 
preservation  of  the  tooth,  as  in  a  lone  molar  for  clasping  pur- 
poses or  for  mastication,  be  the  prime  consideration,  all  expe- 
rience indicates  that  an  amalgam  which  will  discolor,  better 
accomplishes  this  end.  Therefore,  in  such  casee,  and  particu- 
larly if  there  are  "  submarine  "  complications,  alloys  of  silver, 
tin,  and  copper  should  be  used  in  preference  to  those  contain- 
ing gold,  platinum,  zinc,  or  —  worst  of  all  —  cadmium. 

Fifth.  Edge-strength  Test. —  For  the  suggesting  and  devising 
of  this  important  "  test,"  I  must  claim  for  myself  the  original- 


TESTS    FOR    AMALGAM.  77 

ity.  The  necessity  of  good  "  edge-strength  "  is  recognized  in 
connection  with  all  filling  materials  except  gutta-percha ;  but 
in  no  other  material  in  which  it  can  be  regarded  as  mainly  a 
physical  characteristic,  is  it  so  important  as  in  amalgam. 

In  the  working  of  tin,  a  certain  degree  of  edge-strength  can 
be  given  by  superior  manipulation.  In  the  working  of  gold,  a 
marvellous  degree  of  edge-strength  can  be  given  by  superior 
manipulation;  while  a  sufficiency  of  edge-strength  can  be  given 
for  a  majority  of  fillings  by  very  ordinarily  good  manipulation. 
The  oxy-chloride  of  zinc-fillings  are  not  expected  to  have  any 
sustaining  degree  of  edge-strength,  nor  to  retain  for  any  great 
length  of  time  even  the  edge  which  is  first  obtained.  The  zinc- 
phosphates,  though  capable  of  possessing  in  considerable  de- 
gree this  desirable  attribute,  are  quite  deficient  as  at  present 
in  the  market.  Gutta-percha  is  accepted  as  possessing,  practi- 
cally, no  edge-strength.  Amalgam,  therefore,  is  the  only  "plas- 
tic" which  can  to  any  extent  be  depended  upon  for  edge- 
strength. 

It  is  this  fact,  superadded  to  the  recognized  need  for  the 
quality,  which  made  work  upon  this  point  of  such  serious  im- 
port to  the  "  plastic-fillers." 

In  this,  perhaps,  more  than  in  any  other  direction,  was  it 
necessary  that  experimenting  should  be  done  with  the  attain- 
ment of  results  which  should  be  unquestionable. 

The  usual  method  of  making  "buttons,"  and  testing  the 
edge-strength  by  breaking  them  with  the  thumb-nail,  was  re- 
garded as  evidently  unscientific  and  unsatisfactory,  notwith- 
standing its  modicum  of  sturdy  practicality.  The  instrument 
shown  in  the  illustration  was,  therefore,  devised. 

Ingots  of  amalgam  for  "  edge-strength  tests  "  are  made  of  the 
definite  shape  and  size  given  by  the  bevel-edged  matrix.  Into 
this  matrix  samples  of  the  different  amalgams  are  packed  as 
though  for  fillings ;  endeavoring  to  give  to  each  the  greatest 
edge-strength  of  which  it  is  capable.  After  allowing  the  "test" 
to  harden  thoroughly,  it  is  taken  from  the  matrix  and  screwed 
firmly  in  position  by  the  thumb-screw  lever.  The  chisel 
shaped  punch-rod  is  then  rested  upon  the  edge  of  the  sample, 
and  the  rolling-pea  is  slowly  pushed  out  upon  the  graduated 
scale-beam.  The  indicator  shows  the  point  at  which  "  crush  " 


78  PLASTICS    AXD    PLASTIC    FILLING. 

or  "  fracture  "  occurs ;  and  thus  is  graded  the  relative  "  edge- 
strength,"  with  its  accompanying  "  toughness  "  or  "  brittleness." 

By  this  test  is  also  graded  the  relative  ratio  of  "  setting " 
within  the  bounds  of  "  burnish  possibility."  Thus,  for  exam- 
ple, a  sample  of  "Townsend's"  is  packed  and  allowed  to  set  for 
fifteen  minutes;  it  is  then  carefully  removed  and  "tested"  with 
a  light  rolling-pea.  A  sample  of  "  Hardman's  "  is  packed  and 
tested  also,  after  having  set  for  the  same  length  of  time ;  then 
another  sample  of  "  Townsend's"  is  allowed  to  set  for  thirty 
minutes,  and  is  then  tested ;  and  a  duplicate  of  "  Hardman's  " 
is  also  tested  after  thirty  minutes'  setting.  It  will  be  seen  that 
by  this  method  gradations  may  be  obtained  which  will  defi- 
nitely "  rank  "  any  amalgam,  and  that,  too,  beyond  reasonable 
probability  of  error. 

Sixth.  Tooth-conserving  Test. — This,  after  all,  is  the  grandest 
test  of  amalgam.  It  is  the  test  which  can  only  be  done  in  the 
mouth  •  it  is  the  test  which  has  been  given  it  in  the  most  try- 
ing manner,  asking  of  it  to  "  do "  when  everything  else  had 
not  done ;  asking  of  it  to  "stand"  when  everything  else  had 
fallen;  asking  of  it  to  "save"  when  everything  'else  had 
failed! 

And  how  has  it  responded?  If  /were  to  say,  "nobly!"  I 
might,  very  truthfully,  be  regarded  as  an  interested  witness,  for 
amalgam  has  largely  contributed  to  my  success  in  the  difficult 
task  of  saving  everything  that  had  been  hopelessly  abandoned/ 

So  I  will  not  testify  ! 

Some  of  the  blackened  "  shells  of  teeth  "  that  were  filled 
with  coin  amalgam  more  than  forty  years  ago,  testify.  The 
thousands  of  teeth  that  have  been  filled,  apologetically,  testify. 

The  hundreds  of  teeth  that  have  been  filled  with  the  assertion 
and  the  full  belief  that  they  would  "  last  only  a  year  or  two," 
and  have  lasted  ten  and  sometimes  twenty  —  testify. 

Dentists  also  testify.  In  the  face  of  opposition ;  in  spite  of 
vituperation  ;  in  contempt  of  malediction  ;  in  defiance  of  threat- 
ened professional  ostracism,  dentists  have  testified.  Admissions 
of  deadly  antagonism,  without  one  particle  of  knowledge  or  ex- 
periment, have  been  wrung  from  some  —  that  is  testimony; 
the  possibility  of  its  utility  "in  certain  cases  "  has  been  ad- 
mitted by  others  —  that  is  testimony ;  good  words  have  been 


TESTS    FOR    AMALGAM.  79 

ventured  for  it,  slantwise,  ever  and  anon,  even  by  respectable 
members;  it  is  believed  by  them  "to  be  valuable  as  a  filling 
material  v.-hen  used  with  proper  care  and  discrimination"! ! ! 
that  is  testimony. 

But  others  have  spoken  heartily,  out  of  their  love  for  truth, 
out  of  their  knowledge  gained  by  years  of  experiment  and  ob- 
servation. 

Dr.  S.  P.  Cutler  says,  "  Take  any  mouth  or  any  number  of 
mouths,  with  decayed  teeth  in  every  and  all  stages  of  decay, 
and  let  any  first-class  operator  fill  all  decayed  teeth  on  one  side 
of  the  mouth  with  gold,  and  all  on  the  other  with  best  quality 
of  amalgam,  say  all  back  of  cuspids,  the  same  skill  and  care 
being  used  in  both,  and  await  results." 

"In  my  opinion,  based  upon  observation,  the  side  of  the  mouth 
filled  with  amalgam,  in  ten  or  twenty  years,  will  be  found  in  a 
better  condition  than  the  other." 

Dr.  C.  C.  Allen  says,  "  If  my  life  and  fortune  depended  upon 
the  saving  of  a  tooth  merely,  without  regard  to  its  appearance, 
I  would  fill  it  with  amalgam" 

Dr.  J.  Washington  Clowes  says,  "Thus  imperfectly  have  I 
discussed  amalgam.  Conceived  in  weakness,  brought  forth  and 
nurtured  by  empiricism,  traduced,  maligned,  denounced  by 
professionals  in  high  places,  malused,  abused,  and  buffeted,  it 
has  come  to  be  a  power  in  the  land."  "  Out  of  weakness  it  has 
grown  strong,  and  the  very  vices  of  its  origin  are  covered  by 
the  mantle  of  its  virtues."  "  The  combination  of  metals  known 
as  amalgam  is  singular  in  this :  That  of  all  the  faults  it  is  said 
to  possess,  of  all  the  harm  it  is  said  to  have  done,  it  is  as  free 
and  innocent  as  the  child  unborn." 

"  I  am  impelled  to  take  up  its  defense  at  this  time  by  a  sense 
of  duty  which  I  owe  to  it  and  to  every  people,  wherever  in 
the  wide  world  the  voice  of  its  calumniators  has  been  heard, 
believed,  and  had  power  to  alarm." 

"  I  know  of  no  worthier  act  than  the  performance  of  duty, 
no  higher  aspiration  than  the  enunciation  of  truth,  no  attain- 
ment more  eminent  than  professional  excellence.  By  the  sense 
of  duty  well  performed,  by  the  truth  fearlessly  proclaimed,  by 
the  excellent  idealized  and  labored  for,  I  beseech  you,  brethren, 
be  not  henceforth  faithless,  but  believing." 


80  PLASTICS    AND    PLASTIC    FILLING. 

This  is  the  sound  of  the  advocates  of  amalgam.  It  pours 
forth  from  the  heart  with  the  earnestness  of  conviction;  it 
comes  from  the  brain  stamped  and  milled  as  the  coinage  of  in- 
telligence;  it  has  the  "ring  of  the  true  metal,"  while  the 
"valuable,  if  used  with  care  and  discrimination"  has  the  feeble 
tinkle  of  the  truckler  to  professional  prejudice.  Amalgam  has 
proven  itself  to  be  a  notable  tooth-saver. 


ARTICLE   VIII. 
PREPARATION  OF  CAVITIES. 

THE  very  frequent  occurrence,  in  discussions,  of  the  statement 
that  "  cavities  are  prepared  for  amalgam  with  the  same  care 
as  for  yold"  is  significant  of  the  fact  that  gold  preparations  are 
esteemed  as  essential  to  the  highest  future  integrity  of  the  fill- 
ing. In  fact,  the  remark  is  usually  made  in  that  semi-apologetic 
tone  which  seems  to  intimate  the  presumption  that  for  amalgam 
the  preparations  might  be  thought  to  be  made,  ordinarily,  after 
such  manner  as  would  be  in  consonance  with  the  probable  in- 
ferior manipulative  ability  of  the  "plastic-filler;  "  and  it  is  de- 
sired that  fellow-members  shall  be  aware  that,  although  the 
filling  to  be  introduced  is  inferior  to  those  generally  inserted, 
the  "  preparation  "  is  of  that  superior  order  usually  indulged  in 
by  the  speaker. 

The  worker  in  amalgam  recognizes  that  every  principle 
which  governs  the  preparation  of  cavities  for  gold  fillings  is 
ignored  in  the  preparation  of  cavities  for  amalgam.  He,  there- 
fore, would  not  prepare  his  cavities  for  amalgam  with  the 
"  same  care  as  for  gold  "  any  more  than  he  would  prepare  cav- 
ities for  gold  with  the  same  care  as  for  amalgam.  He  prepares 
his  cavities  for  gold  fillings,  with  care,  for  gold,  and  his  cavities 
for  amalgam  fillings,  with  care,  for  amalgam,  without  any 
thought  of  comparison  of  the  one  ivith  the  oilier,  because  there  is 
nothing  in  common  between  the  two  preparations. 

In  preparing  for  gold,  the  governing  principles  result  in  the 
making  of  free  ingress  to  cavities ;  of  flush  walls  with  antago- 
nizing bearings ;  of  retaining  grooves  and  pits ;  of  cavity  shape 


PREPARATION    OF    CAVITIES.  81 

triflingly  larger  at  mouth  than  at  base ;  and  in  the  absence  of 
undercuts  and  overhanging  edges;  all  is  done  to  the  end  that 
the  packing  of  the  gold  shall  be  accomplished  without  danger 
of  interstice  between  filling  material  and  cavity  wall  —  leakage 
is  the  bugbear  of  the  gold-filler. 

In  preparing  for  amalgam,  the  governing  principles  result 
in  the  making  of  cavities  without  angles ;  with  no  flush  walls ; 
few,  if  any,  pits  ;  with  cavity  shape  decidedly  larger  inside  than 
out;  with  concave  undercuts  and  largely  overhanging  edges; 
in  short,  he  aims  to  make  his  cavity  a  concavity  to  the  extent 
of  his  ability.  Why  is  this  ?  Because  he  recognizes  the  sphe- 
roiding  tendency  of  his  material ;  he  recognizes  that  it  "  draws  " 
from  angles  and  from  straight  walls ;  he  wants  to  shape  it  and 
to  place  it  as  it  wants  to  stay.  Bulging  and  crevicing  are  the 
bugbears  of  the  amalgam -filler. 

In  the  preparation  of  cavities  for  gold,  it  is  taught  to  remove 
all  decay  which  is  possible,  compatible  with  safety  to  the  pulp. 
This  is  done  for  the  double  purpose  of  a  firm  foundation  upon 
which  to  rest  the  filling,  and  for  the  insuring  of  solid  packing 
to  prevent  leakage.  So  important  is  this  to  the  success  of  gold 
work,  that  immediately  upon  the  acceptance  of  the  "  leaving 
of  decay "  as  essential  to  the  proper  preparation  of  certain 
kinds  of  cavities  —  a  practice  which  was  fought  almost  as  bit- 
terly as  was  amalgam,  but  which  Prof.  Arthur  pushed  to  dis- 
cussion and  acceptance  with  all  the  energy  of  strong  conviction, 
—  such  devices  as  golden  arches  made  of  pellets,  concavo-convex 
disks  of  plate,  etc.,  were  suggested  as  supports  for  condensa- 
tion. 

In  the  preparation  of  cavities  for  amalgam  all  this  is  lost 
sight  of — the  retaining  edges,  the  deep  curves,  the  "holding 
power  "  of  properly  prepared  periphery,  make  the  mind  of  the 
amalgam-worker  easy  on  the  score  of  plug-retention,  and  he, 
truly,  bestows  as  much  attention,  care,  and  thought  upon  not 
removing  decay  as  the  gold-worker  does  upon  its  removal ! 

In  a  recent  society  discussion  upon  amalgam,  it  was  asked, 
il  What  is  the  theory  of  the  action  of  amalgam  upon  the  teeth?" 
The  reply  of  one  of  the  most  distinguished  of  those  present  is 
reported  to  have  been  that  "  Teeth  are  rendered  calcified  by 
it,"  and  are  "  saved  by  the  deposits  of  lime  salts  from  the  fibrin 
6 


82  PLASTICS    AND     PLASTIC    FILLING. 

in  the  tubules.  I  have  never  seen  this  excessive  hardening 
under  gold."  This  is  unquestionably  a  statement  of  facts. 
Decayed  dentine  is  recalcified,  very  usually  under  amalgam ; 
and,  although  I  have  frequently  seen  exceedingly  hard  recal- 
cification —  very  dark  —  under  gold,  yet,  the  characteristics  of 
the  recalcified  tissue  are  sufficiently  dissimilar  to  warrant  me 
in  saying  that  I  have  never  seen  such  calcification  under  gold 
as  I  usually  find  under  amalgam. 

"With  the  S.  B.  Palmer  theory  of  "  compatibility,"  this  seems 
to  us,  of  the  "  New  Departure,"  as  capable  of  being  reasonably 
commented  upon  beyond  the  confines  of  mere  statement  of 
result.  Agreeing  with  Prof.  Arthur,  that,  "  in  a  majority  of 
cases,  if  the  cavity  be  so  filled  as  to  preclude  leakage,  caries 
will  not  progress  even  though  decayed,  dead,  and  decomposed 
dentine  be  left  therein"  —I  regard  gold  as  a  means  for  the 
arrestation  of  decay  by  this  method. 

In  teeth  of  good  structure  it  precludes  "  leakage ;  "  it  acts  as 
a  mechanical  barrier  to  the  continuance  of  that  decalcification 
of  dentine  which  has  been  proven  to  be  beyond  the  power  of 
the  pulp  to  prevent;  this  being  done,  secondary  calcification 
takes  place.  If  the  matrix  —  decalcified  dentine  —  is  light  in 
color,  the  rccalcification  differs  but  slightly  from  original 
dentine;  if  the  matrix  is  discolored, — and  1  have  left  it  some- 
times very  dark, —  the  recalcification  is'  subject  to  that  con- 
trol, and  I  have  seen  it  almost  as  dark  as  under  some  amal- 
gams. 

In  regard  to  relative  "hardness,"  I  have  nothing  positive 
to  say ;  for  it  is  comparatively  infrequent  that  I  have  to  cut 
recalcified  dentine  ;  but,  in  my  experience,  it  never  has  occurred 
to  me  to  grade  recalcification  under  amalgam  as  harder  than 
that  under  gold.  I  have  seen  it  soft  under  each,  and  intensely 
hard  under  each. 

But,  as  I  have  said,  I  have  never  seen  such  recalcification 
under  gold  as  I  usually  find  under  amalgam.  It  is  this  which 
demonstrates  one  of  the  greatest  differences  between  the  two 
materials  as  filling  materials.  Take  an  ordinary  cavity  in  a 
very  soft  tooth:  the  preparation  is  easily  made;  the  cavity 
walls  are  thick  and  sufficiently  strong ;  either  material  is  well 
inserted  by  any  one  possessing  an  average  amount  of  skill. 


PREPARATION    OF    CAVITIES.  83 

Both  fillings  look  as  though  they  would  do  good  service,  and 
here  the  equality  ends. 

The  gold,  not  liable  to  tarnish,  maintains  its  appearance  of 
integrity  —  it  is  a  thing  of  beauty ;  the  amalgam,  liable  to  tar- 
nish, gradually  loses  its  whiteness  ;  it  gradually  becomes  more 
and  more  discolored  ;  the  surrounding  tooth-structure  partakes 
decidedly  of  this  discoloration;  the  entire  tooth  is  "shaded;" 
it  is  not  a  thing  of  beauty!  But  what  is  the  result?  Prof. 
Arthur  says,  "  If  leakage  is  prevented,  etc.,"  but  in  a  very  soft 
tooth  leakage  cannot  be  prevented;  it  comes  through  the  soft 
tissue  of  the  tooth  itself,  and  moisture  finds  in  gold  an  un- 
changing substance,  resisting  all  approach,  an  "  incompatible  "- 
according  to  our  ideas  —  offering  everything  but  help  in  this 
emergency.  It  usually  is  not  many  years  before  an  examining 
probe  can  readily  be  passed  between  the  filling  and  the  soften- 
ing cavity  walls. 

So,  in  the  very  soft  tooth  filled  with  amalgam,  the  leakage 
cannot  be  prevented,  but,  coming  through  the  tooth-tissue,, 
moisture  finds  itself  in  contact  with  a  material  susceptible  of 
change;  a  material  which,  instead  of  resistance,  offers  decom- 
posing yielding  to  approach;  less  "incompatible"  at  first,  ac- 
cording to  our  ideas,  from  the  metallic  standpoint,  increased 
"  compatibility  "  results  from  the  gradual  formation  of  soluble 
salts  of  silver,  tin,  and  copper ;  these  being  dissolved,  are  taken; 
up  by  the  contiguous  dentine,  which,  with  its  incorporated  me- 
tallic salts,  becomes  so  in  affinity  with  the  amalgam  filling,  with 
its  film  of  "  tarnish  "  —  metallic  salts  —  as  to  insure  almost 
completely  harmonious  apposition  of  tooth-bone  and  filling,  ces- 
sation, practically,  of  decay,  and  recalcification,  with  metallic 
lustre,  of  decalcified  dentine. 

This,  the  amalgam-worker  counts  upon;  he  requires  no  firm 
substratum  as  a  solid  resting-place  for  filling,  but  places  his 
plastic  material,  gentW,  in  perfect  apposition  with  the  soft  den- 
tine, having  faith  to  believe  that  in  due  time  both  will  become 
hard,  and  having  some  definite  theory  upon  which  to  base  the 
probable  realization  of  his  hopes. 

In  order  to  insure  success,  the  amalgam-worker  largely  con- 
fines his  labor  to  the  peripheral  portions  of  his  cavities ;  in  his 
obtunding  of  sensitiveness,  he  mainly  bestows  attention  upon 


84  PLASTICS    AND    PLASTIC    FILLING. 

the  sub-enamel  membrane ;  in  his  cavity  shapings,  his  thoughts 
are  always  upon  spheroiding,  and  by  these  means  having  made 
preparations  in  point  of  fact,  from  the  manipulative,  the  thera- 
peutic, the  theoretic,  and,  by  this  combination,  from  the  scien- 
tific standpoint  —  equal  to  anything  which  could  be  done  for 
gold  —  he,  in  addition  to  all  this,  is  helped  by  his  filling  mate- 
rial, and  thus  the  record  is  made  that  teeth  can  be  saved  with 
amalgam  which  cannot  be  saved  with  gold. 


ARTICLE   IX. 
THE  MAKING  OF  AMALGAM. 

IN  the  earlier  days  of  this  material,  it  was  the  generally  ac- 
cepted method  of  making,  that  the  desired  portion  of  coin 
filings  should  be  placed  in  the  palm  of  the  hand,  and  should 
have  mercury  added  to  it  in  sufficient  quantity  to  admit  of  the 
forming  of  a  plastic  mass  by  kneading  it  with  a  finger  of  the 
other  hand.  To  do  this  properly  is  a  prolonged  and  difficult 
piece  of  work.  If  an  insufficient  quantity  of  mercury  was  first 
added,  and  the  mass,  in  consequence,  was  not  plastic  enough  for 
proper  kneading  and  for  working  as  a  filling,  more  mercury 
was  added,  in  small  portions,  until  the  mass  was  of  the  desired 
consistence.  If  too  much  mercury  was,  at  any  time,  found  to 
be  in  combination  with  the  filings,  a  part  was  squeezed  out  by 
pressure  from  the  finger.  In  this  manner  was  amalgam  made 
for  its  first  twenty-five  years. 

It  is  now  about  twenty-five  or  thirty  years  since  the  mode 
of  making  which  has  been  referred  to,  and  described,  as  the 
"  mortar  "  and  "  washing  "  method,  was  brought  to  the  general 
notice  of  the  profession  by  Prof.  Townsend.  It  is  not  claimed 
that  the  ideas  originated  with  him,  but,  on  the  contrary,  it  is 
admitted  that  the  formula  for  alloy  and  the  process  of  "wash- 
ing "  were  both  given  Prof.  Townsend  by  Dr.  Hunter,  of  Cin- 
cinnati. I  do  not  know  whether  these  originated  with  Dr. 
Hunter;  but  it  has  been  stated  that  others  were  then  using  the 
so-called  "  improved  "  formula  and  method. 

It  was  but  few  vears  —  three  or  four  —  before  the  idea  of 


THE    MAKING    OF     AMALGAM.  85 

alcoholic  cleansing  was  so  forcibly  attacked  that  it  largely  lost 
its  prestige.  As  early  as  1859,  it  was  suggested,  by  Dr.  James  E. 
Garretson,  that  chloride  of  zinc  should  be  added  to  the  filings 
and  mercury  in  the  mortar,  and  that  these  be  rubbed  up  to- 
gether and  the  chloride  of  zinc  be  then  washed  out  by  water. 
This  made  a  beautifully  white  filling,  which  retained  its  color  in 
many  cases  for  quite  a  long  time,  and  which  seemed  even  more 
preventive  of  tooth  discoloration  than  of  tarnish  to  the  face  of 
the  filling. 

For  the  reason  that  the  thorough  removal  of  the  peculiarly 
disagreeable  taste  and  "feel"  of  the  chloride  of  zinc  was  diffi- 
cult, I  instituted  a  series  of  experiments  —  reported  in  1861  — 
which  I  concluded  by  the  adoption  of  chloride  of  sodium 
(common  salt),  used  practically,  as  was  the  chloride  of  zinc  — 
washed  out  by  water. 

As  my  experiments  progressed  in  the  direction  of  silver  ad- 
ditions to  alloy,  the  "  washing  "  became  less  effective  in  pre- 
venting discoloration,  but  cotemporaneously  with  this  the  de- 
mand for  "  lining  "  cavities  increased,  so  that  in  the  course  of 
ten  or  twelve  years  I  had  abandoned  "washing  "  as  needless,  and 
had  instituted  "  lining "  with  oxy-chloride  of  zinc  quite  uni- 
versally, especially  in  front  teeth.  It  remained,  however,  for 
Mr.  Fletcher,  of  England,  to  demonstrate  that  "  washing  "  was 
absolutely  detrimental,  as  it  produced  a  condition  of  amalgam 
which  greatly  facilitated  and  increased  leakage. 

Immediately  upon  his  announcement  of  this  fact,  I  made  a 
line  of  duplicate  work  upon  this  matter,  and  found  that  my  re- 
sults corroborated  his  conclusions  most  positively.  After  wash- 
ing, either  Avith  alcohol  or  water,  the  amalgam  would  permit 
leakage  in  an  extraordinary  manner,  both  quickly  and  in  large 
degree,  and  this,  too,  although  the  mass  was  not  only  ordinarily 
dried  with  a  napkin  —  as  was  the  custom — but  even  when  it 
was  attempted  to  make  a  thorough  drying  by  using  several  hot 
napkins  consecutively.  It  therefore  is  concluded  that  "  wash- 
ing" —  so  far  from  being  useful  —  is  positively  detrimental. 

In  regard  to  the  mortar-make,  my  conclusions  have  been  very 
different,  for  with  all  changes,  and  having  tried  all  suggestions 
modifying  this,  I  yet  adhere  to  it.  In  Article  V.  reference  has 
been  made  to  the  proposed  mixing  of  alloys  with  the  smallest 


86  PLASTICS    AND    PLASTIC    FILLING. 

possible  amount  of  mercury ;  that  thus  the  amalgam  be  made 
"dry,"  as  it  is  termed ;  that  the  result  be  in  the  form  of  powder, 
and  that  it  be  then  placed  in  cavities  and  rendered  plastic  by 
working  with  heated  instruments.  As  this  method  is  almost  im- 
possible of  practice  in  upper  teeth,  and  particularly  in  difficult 
and  inaccessible  cavities,  the  ingenious  devices  of,  first,  amalga- 
mating by  succussion  —  placing  the  filings  and  small  proportion 
of  mercury  in  a  little  bottle  and  shaking  them  together  into 
powder  —  and,  second,  moulding  the  powder  into  pellets  by  pres- 
sure, using  for  this  purpose  a  small  cylindrical  matrix  and 
plunger,  were  suggested  by  Mr.  Fletcher. 

For  the  requirements  indicated,  these  methods  are  certainly 
the  best  that  have  ever  been  offered,  but  their  necessity  is  based 
upon  the  fact  that  the  alloys  to  be  so  treated  are  most  largely 
composed  of  tin.  With  this  ingredient,  it  has  been  shown  that 
slowness  of  setting,  loss  of  edge-strength,  and  tendency  to 
spheroiding,  have  all  to  be  combated,  and  this  work  is,  un- 
questionably, aided  most  materially  by  using  a  minimum  of 
mercury ;  but,  as  in  the  accomplishment  of  this  purpose  by  this 
method,  an  amalgam  —  even  in  pellet  form  —  of  such  consist- 
ency as  to  necessitate  its  manipulation  by  heated  instruments 
is  afforded,  and  inasmuch  as  every  such  complication  is  disad- 
vantageous from  the  operative  standpoint  of  mutual  comfort, 
it  has  been  essayed  to  arrive  at  equally  good,  and  if  possible 
better,  results  by  methods  which  will  permit  of  desirable  plas- 
ticity and  of  cold  working. 

Furthermore,  it  is  contended,  and,  from  experience,  I  think 
with  reason,  that  an  amalgam  is  better  —  more  thoroughly  an 
amalgam,  more  homogeneously  plastic,  tougher,  capable  of 
being  more  readily  and  more  properly  manipulated,  and  capa- 
ble of  producing  better  "  testings  "•  — if  amalgamated  upon  the 
principle  of  mercury  melting  at  ordinary  temperature. 

In  this  process,  mercury  is  added  to  the  filings  in  sufficient 
quantity  to  make  a  plastic  mass  which  shall  meet  the  varied 
requirements  of  "plastic-filling."  One  of  the  most  important 
of  these  requirements  is  that  of  easy  introduction  ;  and  what- 
ever else  may  be  accomplished  by  the  "powder"  form  of  amal- 
gam, this  certainly  is  seriously  interfered  with.  But,  again,  the 
other  requirements  of  quick  setting,  non-shrinkage,  strength  of 


THE    MAKING    OF    AMALGAM.  87 

edge,  and  maintenance  of  color,  are  all  essentials  to  the  aesthetic 
worker ;  and  it  is  for  the  obtaining  of  these  that  the  fine  work 
on  alloys  has  been  done  and  is  continually  progressing.  As  I 
have  previously  intimated,  those  operators  who  have  used  such 
alloys  as  Hardman's,  Lawrence's,  and  Standard  have  found  no 
need  for  powder-like  amalgam ;  and,  what  is  more,  they  have 
made  results,  in  quantity,  with  their  plastic,  easy-working  mass, 
which  compare,  most  favorably,  with  any  of  the  most  excep- 
tional successes  of  the  "dry-mixed"  amalgams. 

Having  by  the  addition  of  silver  counterbalanced  largely  the 
shrinkage  of  the  plastic  mass,  and  having  by  the  addition  of 
gold  still  more  controlled  it  and  assured  a  better  edge-strength 
and  a  better  maintenance  of  color,  it  is  permitted  that  we  may 
make  the  mass  of  such  consistency  as  will  insure  that  facility 
of  introduction  and  complete  manipulation  which  has  proven 
itself,  in  practice,  to  be  adequate  to  the  comfortable  saving  of 
dreadfully  decayed  teeth. 

It  is  found,  experimentally,  that  in  proportion  as  alloys  are 
good,  so  will  they  tolerate  a  large  admixture  of  mercury ;  and, 
indeed,  it  may  be  stated  much  more  strongly,  that  they  will 
require  a  larger  relative  proportion  of  mercury  for  proper 
working. 

The  reason  for  this  is  evident;  for,  as  the  easily  melted 
metal,  tin,  is  replaced  by  those  which  are  fused  with  diffi- 
culty, as  silver,  gold,  and  copper,  it  naturally  requires  more 
of  the  amalgam  making  component  to  effect  the  desired 
fusion.  '  . 

I  do  not  pretend  to  say  that,  even  with  these  good  alloys, 
the  minimum  of  mercury,  and  the  working  in  the  powder  form 
with  heated  instruments,  would  not  produce  a  filling  which 
might,  theoretically,  be  better  than  one  made  with  the  larger 
proportion  of  mercury ;  but,  for  practicality,  I  must  strongly 
urge  the  latter,  as  that  form  of  amalgam  which  will  be  more 
conducive  to  such  results  as  will  be  most  satisfactory  both  to 
patients  and  operators. 

Beside  regarding  the  plastic  mass  as  the  best  form  in  which 
to  use  amalgam,  and  the  "  mortar-mix "  as  better  than  the 
"hand-mix,"  from  the  greater  cleanliness,  facility,  and  prompt- 
ness with  which  the  amalgam  is  made,  it  is  essential  to  the  best 


88  PLASTICS    AND    PLASTIC    FILLING. 

result,  with  any  amalgam,  that  the  mix  shall  be  accomplished 
in  definite  proportion  with  one  admixture. 

If  a  certain  proportion  of  mercury  and  a  certain  proportion 
of  filings  mixed  and  rubbed  together  are  known  to  make  an 
amalgam  which  responds  in  a  superior  manner  to  the  varied 
tests  for  excellence,  it  is  by  all  means  desirable  that  the  two  be 
placed  together  and  made  into  amalgam  in  those  definite  pro- 
portions. If  a  certain  definite  result  is  accomplished  in  a 
given  time  by  the  rubbing  together  of  these  two  —  mercury 
and  filings  —  at  one  admixture,  the  same  definite  result  cannot 
be  accomplished  in  the  same  given  time  by  the  gradual  addition 
of  alternating  portions  of  first  one  ingredient  and  then  the 
other.  And  yet  this  is  the  usual  manner  in  which  amalgam  is 
made  —  filings  or  merciiry  are  placed  in  either  hand  or  mor- 
tar, and  the  other  ingredient  is  added  in  such  proportion  as  is 
thought  right.  If  the  mass  is  too  plastic,  and  is  more  in  quan- 
tity than  is  judged  sufficient,  the  surplus  mercury  is  squeezed 
out,  and  with  it  indefinite  proportions  of  metals,  which  de- 
stroys the  harmony  of  mixture  in  alloy  just  in  proportion  to 
its  original  exactness.  If  the  mass  is  too  plastic,  and  all  is 
required,  more  filings  are  added.  If  it  be  then  not  sufficiently 
plastic,  more  mercury  is  added.  Now  all  the  time  that  this 
work  is  being  done,  another  work  is  doing  —  the  work  which  is 
in  progress  on  the  part  of  the  ingredients ;  that  work  which 
eventuates  in  the  proper  hardening  of  the  amalgam  mass  when 
it  is  properly  incorporated. 

The  overheating  by  combining  with  too  much  mercury  melts 
out  certain  of  the  ingredients  in  unknown  quantities.  If  the 
alloy  is  a  two-metal  alloy,  combined  without  regard  to  test  re- 
sults, of  course  comparatively  little  injury  will  ensue;  the  ma- 
terial, not  being  good,  cannot  be  made  very  much  less  good; 
but  in  a  fine  alloy,  compounded  with  great  care  and  in  such 
proportions  as  give  excellent  test  results,  the  withdrawal  of 
any  proportion  of  any  of  its  ingredients  is,  presumptively,  det- 
rimental, and  the  withdrawal  of  indefinite  quantities  of  all  its 
ingredients  is,  as  I  have  said,  injurious  in  degree  just  in  pro- 
portion to  its  original  excellence. 

The  overcooling  by  addition  of  too  much  filings  has  just  the 
opposite  effect ;  it  chills  the  mercury  in  such  wise  as  to  prevent 


THE    MAKING     OF    AMALGAM.  89 

a  given  amount  from  doing  its  proper  work  of  fusion.  This 
is  distinctly  shown  in  the  prompt  manner  in  which  an  insuf- 
ficiently plastic  mass  of  amalgam  will  "take  up"  mercury. 
Old  alloy,  long  filed,  will  take  up  by  this  unscientific  mode  of 
mixing  as  much  mercury  as  new  alloy,  freshly  filed,  which  is 
about  one-fifth  more  than  is  required  to  make  a  good  plastic 
amalgam.  This  at  once  transforms  an  excellent  amalgam  into 
acomparatively  poor  one. 

Therefore,  it  is  directed  to  prepare  amalgam  BY  WEIGHT  in 
such  proportions  as  have  been  found  upon  trial  to  make  the 
mass  jmt  right  for  working  in  any  given  case.  This  does  not 
direct  that  the  weighing  shall  be  by  weights,  but  by  proportions; 
and  it  will  be  noticed,  in  the  weighing  of  different  alloys,  that 
different  proportions  of  mercury  will  be  required  for  each  class. 
As  in  the  "quality  test,"  this  work  will  at  once  grade  any  al- 
loy, subject  to  modifying  influences  —  admixtures  of  cadmium, 
etc. —  which  have  been  indicated;  and,  governed  by  these,  it 
will  require  for  first  or  lowest  grade  of  two  metal  alloys  —  tin 
and  silver  —  about  37  to  39  per  cent,  of  mercury ;  for  second 
grade  —  tin,  silver,  and  gold  —  about  41  to  43  per  cent.;  for 
third  grade — silver,  tin,  and  copper  —  about  46  to  48  per  cent.; 
for  fourth  grade  —  silver,  tin,  copper,  and  gold,  or  tin,  silver, 
gold,  and  zinc  —  about  48  to  50  per  cent,  of  mercury. 

This  percentage  of  mercury  is  given  as  average,  and  may  be 
diminished  a  little  for  perfectly  easy  work  in  very  accessible 
cavities,  but  must  be  increased  a  little  for  that  increase  of 
plasticity  which  is  demanded  for  acceptable  working  in  the 
difficult  and  delicate  manipulation  inseparable  from  the  filling 
of  inaccessible  cavities  in  frail  and  sensitive  teeth. 

In  weighing,  for  the  making  of  amalgam,  the  usual  small 
brass  scales  of  the  jeweler  is  all  that  is  required,  though  several 
devices  especially  for  this  purpose  are  for  sale.  The  desired 
quantity  of  mercury  for  any  given  "  make  "  should  be  placed 
in  one  scale,  and  the  beam  should  then  be  sufficiently  depressed 
upon  the  side  of  the  alloy  by  pouring  the  requisite  quantity 
of  filings  into  the  other  scale.  It  will  be  understood,  that  for 
first  grade  alloys  the  beam  will  have  to  be  notably  depressed ; 
for  second  and  third  grade  alloys  the  depression  will  be  less 
and  less ;  for  fourth  —  or  highest  —  grade  alloys  the  beam  will 


90  PLASTICS    AND    PLASTIC    FILLING. 

deviate  but  slightly,  if  at  all,  from  the  horizontal.  From  the 
scales,  the  mercury  and  filings  can  be  poured,  successively, 
into  the  mortar ;  and  this  possibility  should  be  provided  for  in 
any  piece  of  weighing  apparatus.  If  the  beam  is  a  fixture, 
the  scale-plates  should  be  movable,  and  in  no  case  should  the 
scale-plates  or  receptacles  for  the  mercury  and  filings  be  se- 
cured to  the  beam,  as  this  prevents  emptying  them  in  any 
other  way  than  simultaneously.  The  scale-plates  should  be 
made  of  material  which  will  not  be  affected  by  the  mercury, 
as  ivory,  glass,  porcelain,  or  brass. 

This  use  of  scales,  instead  of  being  troublesome,  can  hardly 
fail,  upon  trial,  to  be  accepted  as  the  easiest  and  only  reliable 
way  for  promptly  securing  accurate  proportions  in  the  prepara- 
tion of  amalgam. 

The  proportionate  quantities  of  ingredients  having  been  ob- 
tained, they  should  be  placed  in  a  small  ground  glass  mortar. 
For  this  use  the  porcelain  mortar  has  been  recommended  and 
glass  mortars  condemned ;  but  this  has  been  from  the  fact  that  the 
glass  mortars  were  used  smooth,  and  in  such  it  is  almost  impos- 
sible to  make  an  amalgam;  but  if  the  glazed  surface  is  delicately 
taken  off  the  inside  of  the  glass  mortar,  it  will  prove  much 
superior  to  porcelain.  In  porcelain  mortars,  the  face  of  the 
mortar  discolors  most  markedly  and  disagreeably ;  the  amal- 
gam adheres  in  specks  upon  the  sides,  and  it  is  impossible  to 
remove  it  completely.  In  ground  glass  mortars,  the  face  is 
easily  kept  nicely  clean,  and  the  amalgam  mass  is  readily 
removed  without  much  effort. 

The  pestle  should  also  be  of  glass,  and  the  glaze  should  be 
removed  from  its  bulbous  portion.  It  is  also  much  better  that 
the  little  knob  on  the  small  end  of  the  pestle  be  broken  off  and 
the  pestle  be  inserted  into  a  wooden  handle  —  hard  wood  —  as 
this  gives  one  a  power  for  making  the  amalgam  which  cannot 
be  obtained  from  the  ordinary  glass  pestle  of  small  size. 

Having  the  filings  and  mercury  in  the  mortar,  and  having 
carefully  removed  any  particles  of  amalgam  which  may  be 
adherent  to  the  pestle  from  previous  makings,  the  filings 
should  be  gradually  incorporated  with  the  mercury.  This 
is  done  by  retaining  the  mercury  in  the  centre  of  the  bottom 
of  the  mortar,  and  by  a  circular  motion,  occasionally  reversed, 


THE    MAKING    OF    AMALGAM.  91 

drawing  in  the  filings  little  by  little.  This  should  be  accom- 
plished with  sufficient  deliberation,  and  yet  with  sufficient  ra- 
pidity, a  procedure  which  can  alone  be  acquired  by  practice. 
The  object  gained  by  this  process  is,  that  in  this  way  the  per- 
centage of  mercury  given  will  "  take  up  "  and  make  a  plastic 
mass  of  the  given  proportion  of  filings,  whereas,  if  the  filings 
are  at  once,  and  without  method,  mixed  with  the  mercury,  it 
will  become  chilled,  and  the  amalgam  will  be  hard,  dry,  and 
crumbly. 

The  rubbing  should  be  both  decided  and  somewhat  pro- 
longed, until  a  smooth  plasticity  is  imparted  to  the  "  make." 
The  possibility  of  nicely  accomplishing  this  result  is  the  indi- 
cation which  governs  the  knowledge  as  to  proper  quantity  of 
mercury.  If  this  result  is  attained  too  easily,  there  is  too 
much  mercury ;  if  it  is  not  attainable,  there  is  an  insufficiency 
of  mercury,  and  a  little  more  should  be  added. 

Amalgamation  being,  to  a  certain  extent,  complete,  any 
amalgam  adherent  to  the  pestle  should  be  scraped  off  into  the 
mortar,  using  a  knife  or  small  spatula  —  of  the  set  of  instruments 
—  for  this  purpose.  The  pestle  is  sometimes  cleaned  by  rub- 
bing it  off  with  the  finger,  but  the  use  of  the  spatula  is  much 
neater,  and  will,  by  practice,  soon  become  habitual. 

The  mass  is  then  gathered  by  the  finger  from  the  mortar 
into  the  palm  of  the  hand,  and  is  kneaded  until  it  becomes  a 
" button."  This  may  seem  a  very  simple  performance,  but  it 
is  one  of  the  best  tests  for  the  plastic-filler.  It  is  almost  unex- 
ceptionable that,  as  the  worker  in  amalgam  takes  his  mass 
from  the  mortar  and  works  it  into  a  "  button,"  so  does  he 
grade  himself  as  skilful  or  unskilful  in  the  working  of  the 
material,  and  so  closely  does  he  do  this  that  an  observing 
expert  will  place  him  to  a  nicety.  It  seems  as  though  all  his 
knowledge  concentrates  itself  upon  this  little  act,  just  as  a 
singer  manipulates  his  "telling  note,"  and,  inversely,  igno- 
rance and  incapacity  will  crop  out  when  one  of  the  uninitiated 
attempts  to  handle  a  "  button."  It  is  the  aim,  then,  by  strong, 
energetic,  decided  effort,  to  knead  partial  amalgamation  into 
homogeneous  plasticity.  The  mass  is  gathered  together  in 
the  palm  of  the  hand  by  the  forefinger  and  thumb  of  the 
other  hand,  and  is  then  squeezed  and  smoothed  into  commenc- 


92  PLASTICS    AND    PLASTIC    FILLING. 

ing  homogeneity  by  a  down  stroke  on  the  forefinger;  then  ma- 
nipulated as  before,  and  again  squeezed  with  the  down  stroke. 
It  is  during  this  manipulation,  oftentimes  repeated,  that  the 
"crepitation"  of  an  amalgam  is  heard.  This  was  referred  to 
in  the  article  on  "  Tests  "  as  "  peculiarly  pleasing  to  the  ini- 
tiated," for  it  is  regarded  as  indicative  of  an  excellent  alloy. 
The  short,  sharp,  decisive  cry  is  something  like  that  produced 
in  the  bending  of  a  bar  of  tin,  and  with  all  the  testings  in 
which  I  have  engaged,  and  even  in  the  daily  work  of  making 
amalgam  for  actual  practice,  it  is  invariably  the  case  that,  when 
it  is  perceived  by  one  who  knows  its  meaning,  the  recognition 
is  immediately  made  manifest  by  facial  expression  of  approval 
or  by  outspoken  words  of  commendation. 

The  "  button  "  having  been  made,  it  should  be  held  in  the 
palm  of  the  non-operating  hand  by  closing  the  fourth  and  little 
fingers  upon  it,  thus  leaving  the  thumb,  fore-,  and  middle  fingers 
free  to  aid  in  operating.  This  is  at  first  by  no  means  an  easy 
thing  for  every  one  to  do,  but  is  acquired,  without  much  diffi- 
culty, by  practice,  and  is  of  decided  importance,  as  it  maintains 
to  the  amalgam  a  degree  of  plasticity,  by  warmth,  which  can- 
not be  utilized  if,  as  is  frequently  the  case,  the  "  button  "  is  laid 
upon  the  operating-table,  and  there  cut  up  into  pieces.  The 
amalgam  is  now  ready  for  insertion. 


AKTICLE   X. 

INSTRUMENTS  FOR   THE  INSERTION  OF  AMALGAM 

FILLINGS. 

WITH  the  idea  that  experience  indicates  the  employment  of 
few  but  accurately  adapted  instruments  as  conducive  to 
expert  manipulation  and  productive  of  superior  results,  I  have 
gradually  introduced,  discarded,  modified,  and  selected  shapes, 
sizes,  and  number  of  instruments  until,  for  daily  routine  work, 
I  have  for  the  last  three  years  had  no  necessity  for  change  or 
addition ;  nor  have  I  seen  the  possibility  of  any  advantageous 
reduction  in  number. 

Based  upon  these  conclusions  is  a  set  of  filling  instruments 


AMALGAM-FILLING    INSTRUMENTS.  93 

for  amalgam,  and,  incidentally,  for  zinc-phosphate  and  gutta- 
percha  stoppings,  the  patterns  for  which  I  have  furnished  for 
manufacture  during  the  past  year.  The  annexed  illustrations, 
with  descriptions  for  use,  will,  I  think,  afford  all  needed  instruc- 
tions to  insure  a  satisfactory  adaptation  of  means  to  ends. 

It  will  be  observed  by  practitioners  who  are  generally  con- 
versant with  instrument  forms  that  I  have  endeavored  to  util- 
ize familiar  shapes  rather  than  devise  new  instruments ;  and  in 
this  I  have  almost  entirely  succeeded.  My  reason  for  so  doing 
is,  that  the  habit  of  use  which  has  been  acquired  in  one  direc- 
tion may  be  made  subservient  in  other  work ;  thus  the  use  of 
the  ball-burnisher,  having  been  acquired  for  the  purpose  of  fin- 
ishing gold  fillings,  may  readily  be  made  subservient  to  the 
packing  of  amalgam  and  zinc-phosphate,  etc. 

To  the  grouping  and  to  the  ideas  of  adaptation  I  have  striven 
to  give  the  impress  of  originality,  and  trust  that  in  this  I  shall 
have  afforded  such  aid  as  is  desired  by  the  inexperienced,  and 
possibly  may  have  been  fortunate  enough  to  give  some  hints 
of  value  even  to  those  of  large  amalgam  experience. 

The  set  consists  of  twelve  instruments,  ten  of  which,  Nos.  1, 
2,  3,  4,  5,  6,  7,  8,  10,  and  11,  are  especially  adapted  to  amal- 
gam work,  and  two,  Nos.  9  and  12,  are  subservient  to  occasional 
incidental  and  frequent  special  requirements  in  plastic  filling. 

It  must  be  noted  that  the  set  is  first  divided  into  three  classes 
—  round  ends,  flat  ends,  and  trimmers  or  separators.  With  these 
three  types  one  is  able  to  meet  all  indications.  These  classes 
arc  subdivided  into 

Round  ends. —  1.  No.  1.  Large  ball-burnisher.  This  is  used 
for  crushing  and  packing  the  pieces  of  amalgam  which  are  suc- 
cessively placed  in  position  —  either  by  thumb-pliers  or  amal- 
gam-carriers —  in  large  cavities  easy  of  access. 

2.  No.  2.  Medium-sized  ball-burnisher.  Used  for  the  same 
purpose  and  in  the  same  manner  as  No.  1  in  medium-sized  cav- 
ities easy  of  access,  and  in  inaccessible  cavities  of  large  size  for 
final  packing  after  the  pieces  of  amalgam  have  been  prelim- 
inarily crushed  by  appropriate  instruments,  —  carriers  or  flat 
ends,  —  also  for  tapping  "wafers"  (see  Article  XI.)  and  smooth- 
ing fillings  upon  the  articulating  faces  of  teeth, —  especially  of 
the  lower  teeth,  —  and  upper  second  and  third  molars. 


94  PLASTICS     AND    PLASTIC    FILLING. 

3.  No.  3.  Small-sized  curved  burnisher.     This  instrument 
is  one  of  varied  usefulness  and  of  frequent  adaptiveiiess.     It 
crushes  and  packs  the  amalgam  in  a  large  proportion  of  cavi- 
ties upon  articulating,  distal,  buccal,  and  labial  faces ;  and  in 
cavities  of  all  sizes  above  minimum  it  is  in  constant  demand. 
It  packs  into  under  cuts,  grooves,  and  corrugations ;  it  crushes 
the  outside  pieces  in  large  cavities  —  especially  buccal  —  and 
packs  them  nicely,  using  its  side;  it  smoothes  the  face  of  buc- 
cal, distal,  mesial,  and  labial  fillings ;  removes  surplus  material, 
and  defines  cervical  edges  of  fillings  extending  below  the  gum ; 
"  wafers  "  buccal  fillings  better  than  any  other  form  of  instru- 
ment, and  becomes,  in  amalgam  work,  an  indispensable. 

4.  No.  4.  Very  small  "  goose-neck  "  burnisher.     This  little 
instrument  is  used  exclusively  in  the  filling  of  very  small  cavi- 
ties.    These  are  usually  in  the  sulci  of  molars  and  bicuspids, 
or  upon  the  necks  of  teeth,  or  in  the  mesial  or  distal  faces  of 
incisors  and  cuspids.     Its  peculiar  form  is  eminently  adapted  to 
this  work,  as  it  is  possible  to  insinuate  it  dexterously  in  spaces 
of  very  moderate  size  between  teeth,  and  then  so  turn  it  as  to 
compress  and  pack  filling  material  in  the  bottom  of  cavities  of 
a  depth  which  is  considerable  in  proportion  to  their  size  of  ori- 
fice.   This  instrument  is  one  of  those  which,  though  not  of  such 
frequent  use  as  some  others,  is,  nevertheless,  the  instrument  for 
which  there  is  no  substitute  when  its  services  are  required. 

As  I  have  spoken  here  of  very  small  cavities  in  front  teeth, 
and  as  it  will  be  some  years  yet  before  the  filling  of  such  cavi- 
ties —  even  in  soft  teeth  —  with  plastics  will  become  generally 
accepted  as  proper  practice,  I  wish  here  to  say  that  some  of  my 
most  decided  successes  during  the  past  ten  years  have  been  made 
by  this  practice.  I  have  scores  of  young  patients  whose  elder 
brothers  and  sisters  had  been  placed  under  the  best  gold  work 
which  our  own  and  other  large  cities  afforded,  and  whose  front 
teeth — particularly  laterals  —  had  been  filled  and  refilled  with 
gold  until  pulp  after  pulp  had  died,  and  tooth  after  tooth  had 
discolored, —  and  all  this  before  they  were  twenty  years  of  age, 
—  whose  teeth  are  of  as  soft,  and  even  softer  structure  than  those 
which  had  been  so  treated,  and  who  are  now  from  sixteen  to 
twenty  years  old,  and  who  are  most  markedly  reaping  the 
benefits  conferred  by  plastic  fillings  in  "  pin-head "  cavities 


AMALGAM-FILLING    INSTRUMENTS.  95 

of  front  teeth,  in  that  they  rejoice  in  handsome-looking  teeth 
containing  living  pulps.  I  have  found  it  comparatively  an 
easy  task  to  care  for  such  teeth  if  the  small  cavities  are  filled 
first  with  plastics  —  gutta-percha  and  "  lined  "  cavities,  with 
amalgam ;  for  the  work  is  easy  and  gentle,  and  thus  the  little 
patients  are  not  demoralized.  The  fillings  last  as  long,  and 
usually  much  longer  than  do  gold  ones;  and  thus  they  do  not 
require  so  frequent  renewal.  And  in  this  way,  when  patients 
reach  that  time  of  life  at  which  they  recognize  and  appreciate 
the  value  of  beautiful  and  entirely  vital  front  teeth,  they  have 
them  in  such  shape  as  that  they  regard  them  as  worth  care  and 
attention. 

I  think  there  is  much  in  this  that  is  worthy  the  careful, 
thoughtful  consideration  of  every  dentist,  and  particularly  of 
those  who  are  now  in  the  earlier  years  of  practice.  They  will 
have  the  teeth  of  the  children  of  this  generation  —  TEETH  BORN 
OF  ARTIFICIAL  DENTURES  !  —  under  their  charge.  It  will  be  for 
them  to  make  the  first  onset  in  antagonism  to  this  wholesale 
loss  of  teeth,  and  my  experience  is,  that  "  compatibility  of  fill- 
ing material  with  tooth-bone"  is  the  foundation  for  tooth  salva- 
tion, and  that  gold  is  eminently  incompatible  with  soft  tooth-bone. 

5.  No.  5.  Medium  sized,  slightly  curved,  round  end.  This 
instrument  is  used  for  crushing  and  packing  in  all  perfectly 
accessible  cavities  of  medium  size,  and  is  particularly  adapted 
for  "  wafering  "  the  faces  of  articulating  fillings.  This  instru- 
ment is  also  the  "  large-sized  probe  "  which  is  frequently  men- 
tioned in  my  pathological  papers  as  proper  for  carrying  all 
thin  fluid  medicaments,  as  hamamelis,  oil  of  cloves,  tincture  of 
aconite,  chloroform,  etc.,  in  the  treating  of  teeth. 

Flat  ends.  —  1.  No.  6  is  a  short,  double  convex,  spatula- 
shaped  instrument.  It  crushes  and  packs  the  superficial  pieces 
of  amalgam  in  accessible  fillings  between  teeth,  where  there  is 
ample  space,  and  particularly  such  wafers  as  are  used  for  these 
fillings ;  it  trims  upon  articulating  faces  in  occasional  cases,  but 
is  mainly  used  as  a  packer  and  smoother. 

2.  No.  7  is  thin,  almost  flat,  slightly  curved,  and  is  used, 
as  is  No.  6,  in  places  where  want  of  space  will  not  permit  of 
using  a  thicker  instrument;  it  is  also  used  as  a  trimmer  in 
such  cases  as  require  No.  6  for  a  packer. 


96  PLASTICS    AND    PLASTIC    FILLING. 

3.  No.  8.  This  is  a  very  useful  instrument,  and  is  used  in 
inaccessible  places  between  teeth ;  distal  or  mesial  cavities ; 
upper  or  lower  teeth;  cavities  extending  to  and  under  the 
gum.  It  is  particularly  adapted  to  the  placing  in  position 
of  portions  of  quite  plastic  amalgam  in  very  inaccessible  cav- 
ities in  both  upper  and  lower  teeth  —  distal  faces  —  after  which 
the  pieces  are  to  be  packed  with  No.  2.  In  wafering  such  fill- 
ings as  these,  No.  8  will  be  found  to  work  admirably  ;  it  is  also 
useful  as  a  smoother  and  shaper  of  fillings  between  teeth,  where 
space  will  permit ;  also  as  a  trimmer  upon  articulating  faces, 
particularly  of  the  lower  teeth. 

Trimmers  or  Separators. —  1.  No.  9.  This  is  a  modification 
of  the  curved  bistoury.  It  is  more  useful  in  zinc-phosphate 
work  than  in  amalgam ;  but  it  is  sometimes  the  case  that  the 
"quick-setters"  harden  too  much  for  the  easy  removal  of  sur- 
plus material.  When  this  is  so,  the  alternating  possibilities 
of  the  convex  and  concave  knife  edo-es  of  No.  9  will  become 

o 

agreeably  apparent. 

2.  No.  10  is  a  modified   Lord   sealer  of  thin   gauge ;    the 
point  is  rounded  so  as  to  prevent  undue  wounding  of  the  gum 
in  the  work  for  which  it  is  appropriated. 

I  have  declared  myself  in  favor  of  "contour  filling.'1  and 
although  this  conclusion  may  be  unjust  to  those  who  "sepa- 
rate "  between  good,  strong  teeth,  I  must  not  be  subjected  to 
their  criticism,  from  the  fact  that  my  work  is  almost  exclusively 
pertaining  to  frail,  soft  teeth.  These  come  to  me  largely  re- 
quiring complete  contouring,  oftentimes  with  two-thirds  and 
even  four-fourths!  of  the  crowns  gone,  and  with  but  little 
masticating  surface  generally, —  from  scarcity  of  teeth  ;  and  I 
aim  to  make  as  close  proximity  of  articulating  faces  —  mesially 
and  distally  —  as  is  possible. 

These  thin  trimmers  or  separators  are  used  for  the  purpose 
of  cutting  the  thinnest  spaces  between  such  crowns,  or  between 
built  crowns  or  fillings,  and  contiguous  teeth.  No.  10  is  espec- 
ially indicated  in  such  work  between  incisors,  cuspids,  bicuspids, 
and  occasionally  even  as  far  lack  as  between  first  and  second 
•molars. 

3.  No.  11.  This  is  also  a  modified  Lord  sealer,  but  it  is  so 
much  modified  that  its  suggester  would  hardly  recognize  it. 


AMALGAM-FILLING     INSTRUMENTS.  97 

It,  however,  becomes  well  adapted  for  the  work  of  cutting  sepa- 
rations between  molars,  both  above  and  below,  by  the  making 
>f  the  obtuse  angle  bend. 

I  would  direct  attention  to  the  fact  that  the  instruments  of 
this  set  are  arranged  for  "universal"  working, —  right  or  left, 
upper  or  lower ;  and  it  is  claimed  that  much  greater  facility 
of  instrumentation  and  celerity  of  operations  are  attained  by 
the  habit  of  constant  work  with  few  instruments,  and  the  non- 
necessity for  the  frequent  change  incident  to  "  right  and  left " 
filling  instruments. 

As  the  complement  to  the  dozen,  I  have  suggested  a  spatula 
which,  for  shape,  balance,  size,  weight,  arid  temper,  seems  to  me 
to  meet  requirements  more  exactly  than  any  heretofore  made. 
If  I  may  judge  from  the  expressions  I  have  already  received,! 
am  correct  in  this,  and  I  therefore  counsel,  more  unhesitatingly, 
the  use  of  an  instrument  which  has  so  many  rivals. 

In  amalgam  work,  the  spatula  is  never  used  for  its  legitimate 
purpose, —  that  of  mixing  the  zinc  plastics ;  but  it  will  occa- 
sionally subserve  excellently  for  smoothing  fillings  between; 
incisors,  particularly  of  the  lower  jaw,  where  space  is  limited, 
and  where  also,  from  the  narrowing  necks  of  the  teeth,  it  is 
peculiar  in  its  shape. 

Besides  the  instruments  for  ordinary  use,  we  have  a  number 
of  ingenious  appliances  as  aids  in  difficult  cases.  These  al- 
most invariably  pertain  to  cavities  in  upper  teeth,  less  or 
more  inaccessible.  The  difficulty  in  such  cases  is  the  placing 
of  the  amalgam  in  position,  and  its  subsequent  crushing  and 
packing,  without  great  loss  from  dropping  of  the  material. 
With  the  ordinary  instruments  this  is  sometimes  impossible 
of  accomplishment,  and  indeed  it  is,  in  some  instances,  exceed- 
ingly difficult  to  do  even  with  the  best  appliances. 

An  instrument  which  is  at  once  simple  and  effective  is  the 
double-end  "  carrier  and  plugger,"  devised  by  Dr.  W.  St.  Geo. 
Elliott, —  No.  1, —  one  end  of  which  —  the  larger  —  is  deeply 
serrated  and  filled  with  amalgam.  This  is  allowed  to  harden, 
and,  as  pieces  of  fresh  amalgam  mass  will  adhere  to  hard 
amalgam,  they  are  thus  readily  carried  into  position,  and 
crushed  with  comparative  ease.  From  the  fact,  of  this  adhe- 
sion, the  instrument  is  called  the  "  Loadstone  amalgam  carrier." 
7 


98  PLASTICS    AND    PLASTIC    FILLING. 

The  other  end  is  serrated.  I  should  prefer  a  smooth  end,  like 
a  medium-sized  ball-burnisher ;  but  even  as  made,  it  is,  I  think, 
a  very  desirable  instrument. 

Another  device  of  the  same  gentleman  is  that  which  is  illus- 
trated as  No.  2,  and  is  at  once  ingenious  and  practical.  Upon 
careful  examination,  the  illustration  will  give  a  very  good  idea 
of  the  working  of  this  instrument,  although  it  is  somewhat 
difficult  to  understand  even  by  description.  Upon  the  end 
of  the  shank  is  placed,  diagonally,  a  cylindrical  hammer-head ; 
around  this  is  a  tube  about  one-fourth  longer  than  the  hammer- 
head— just  the  size  illustrated.  In  this  tube  there  is  a  slot 
"of  about  one-third  its  length,  and  through  this  slot  the  neck 
of  the  instrument  passes.  By  pressing,  with  the  end  of  the 
middle  finger,  the  downwardly  inclined  end  of  the  investing 
tube,  it  is  forced  out  beyond  the  hammer-head,  and  thus  a 
receptacle  for  amalgam  mass  is  made.  By  pressure  on  the 
mass,  retaining  the  finger  in  place,  a  portion  is  forced  into 
the  receptacle.  It  is  then  presented  to  the  cavity,  when,  by 
upward  pressure  upon  the  handle  of  the  hammer,  it  is  forced 
along  through  the  slot,  and  the  amalgam,  ejected  from  the  re- 
ceptacle, is  driven  into  the  cavity  ;  it  is  then  to  be  packed  with 
any  appropriate  filler.  This  is  an  excellent  instrument,  and  is 
in  harmony  with  the  degree  of  plasticity  of  mass  required  for 
the  filling  of  such  cavities  as  it  is  intended  shall  be  filled  by  its 
aid. 

The  only  carriers  which  I  have  seen  that  rival,  in  the  least, 
the  one  described,  are  those  of  Dr.  H.  S.  Chase  —  No.  3  —  and 
Dr.  Thomas  Fry  —  No.  4 ;  both  are  ingenious  and  effective. 
Of  the  other  carriers  illustrated, —  Nos.  6  and  7, —  they  either 
do  not  do  that  which  is  required,  or  do  it  much  less  easily  and 
efficiently  than  those  more  particularly  referred  to. 

Another  form  'of  carrier  is  that  known  as  the  "  Amalgam 
Director"  —  No.  5.  This  is  the  invention  of  Dr.  E.  E.  Mul- 
lett,  and  consists  of  a  peculiarly  shaped  spoon,  with  a  light 
and  appropriate  handle.  It  is  a  very  neat  instrument,  and,  with 
a  little  experience,  will  prove  a  complete  preventive  to  loss  of 
material  in  the  filling  of  these  inaccessible  cavities. 

It  is  as  well  adapted  for  carrying  hard  amalgam  as  it  is  for 
soft  mixed  mass,  and  for  this  reason  is  the  only  one  at  all  use- 


THE    INSERTION    OF    AMALGAM     FILLINGS.          99 

ful  in  wafering.  It  is  particularly  valuable  in  "directing" 
amalgam  into  buccal  cavities  both  superior  and  inferior. 

It  is  not  so  good  for  carrying  amalgam  to  cavities  upon  the 
distal  faces  of  upper  teeth  as  either  the  Chase  or  Elliott  carriers, 
but  it  conduces  to  cleaner  work,  and  is  more  frequently  advan- 
tageous than  any  other  carrier. 

In  this  connection,  I  should  not  omit  the  information  that, 
in  addition  to  many  appliances  in  furtherance,  advantageously, 
of  amalgam  work,  there  are  also  quite  a  number  which  are 
truly  curiosities  in  their  way.  Some  are  made  with  one  end 
about  equidistant  in  form  between  a  toothpick  and  a  sail- 
needle,  and  with  the  other  end  in  the  shape  of  a  little  cup  so 
attached  as  to  be  incapable  of  subserving  any  purpose,  even  if 
there  was  any  purpose  to  subserve ;  others  have  ends  some- 
thing like  shoehorns,  and  handles  like  modern  ice-picks ;  in 
short,  the  singularity  of  form  illustrated  by  these  instruments 
is  only  exceeded  in  degree  by  the  absolute  absence  of  possibil- 
ity that  anything  in  the  way  of  amalgam  working  should  ever 
be  accomplished  by  any  of  them. 


AETICLE   XI. 
THE  INSERTION  OF  AMALGAM  FILLINGS. 

AS  a  large  proportion  of  the  alloys  which  are  at  present  in 
use  will  not  make  amalgams  which  can  be  graded  even  as 
"  good  "  under  testing,  it  is  but  reasonable  to  infer  that  but  few 
operators  have  ever  worked  amalgam  that  would  rank  as  "ex- 
cellent "  upon  its  own  merits.  This  being  the  case,  it  must 
equally  be  presumed  that  the  working  of  fine  amalgam,  differ- 
ing as  it  does,  essentially,  from  that  made  from  all  ordinary  — 
60  tin,  40  silver  —  alloys,  will  have  to  be  acquired  by  nearly 
every  dentist.  Even  those  who  have  had  considerable  expe- 
rience with  such  amalgams  as  are  made  from  Townsend's, 
Walker's,  Arrington's,  etc.,  will  find  such  decided  difference  in 
the  working  of  Lawrence's,  Hardman's,  and  "Standard  "  as  will 
surprise  them.  And  it  should  also  be  known  that  their  working 
of  these  amalgams  must  not  be  regarded  as  forming  any  cri- 


100  PLASTICS    AND    PLASTIC    FILLING. 

terion  as  to  the  possibilities  of  amalgam  work  with  such  material, 
for,  with  observation,  care,  and  practice  they  will  soon  learn  that 
—  as  with  gold  —  the  most  expert  manipulator  makes  the  finest 
results. 

It  is  too  generally  believed  that  an  amalgam  filling  is  an 
amaly am  filling  no  matter  what  it  is  made  from,  how  it  is  made, 
or  in  what  manner  it  is  inserted ;  but  this  is  hardly  more  cor- 
rect than  it  would  be  to  assert  that  a  gold  filling  is  a  gold  fill- 
ing. It  is  true,  that  the  range  between  extremes  is  not  so  great 
in  amalgam  work  as  in  gold  work,  for  the  difference  between  a 
wretched  gold  filling  and  an  admirable  gold  filling  is  so  im- 
mense as  to  be  incredible  to  any  but  proficients  in  such  work ; 
neither  is  the  difference  in  results  between  poor  amalgam  filling 
and  good  amalgam  filling  in  the  least  degree  comparable  with 
that  which  obtains  between  poor  gold  filling  and  good  gold 
filling ;  for  a  good  gold  filling  will  save  even  a  soft  tooth  for  a 
certain  length  of  time,  while  a  poor  gold  filling  may  truthfully 
be  regarded,  from  the  first,  as  a  very  questionable  occupant  for 
a  cavity  in  a  frail  tooth.  On  the  other  hand,  the  cases  now  count 
by  thousands  in  which  confessedly  poor  amalgam  fillings  have 
already  done  longer  and  better  service  in  frail  teeth  than 
equally  confessedly  excellent  gold  fillings  had  done  previously 
in  the  same  teeth.  Neither  is  the  range  between  extremes  in 
manipulative  skill  nearly  so  great  in  amalgam  work  as  it  is  in 
gold  work ;  but  this  I  regard  as  one  of  the  strongest  points  in 
favor  of  amalgam.  It  is  a  fallacy  that  the  profession  of  den- 
tistry bases  its  capability  for  rendering  service  to  suffering 
humanity  most  largely  upon  the  manipulative  skill  of  its  mem- 
bers. In  by-gone  times  this  may  have  been  so ;  but  the  capa- 
bility of  dentistry  to-day  rests  most  largely  —  and  decidedly 
most  largely  —  upon  the  scientific  attainments  of  its  practi- 
tioners in  the  varied  directions  of  anatomy,  physiology,  chem- 
istry, metallurgy,  pathology,  and  therapeutics.  Skilful  manip- 
ulation in  both  operative  and  prosthetic  dentistry  can  never  be 
underrated,  for  it  leaves  its  impress,  as  does  the  finely-cut  die 
upon  the  coin  ;  but  it  can  never  again  be  overrated,  as  it  has 
been  in  the  past ;  it  cannot,  in  future,  grade  the  position  of  the 
dentist ;  it  will  ever  be  recognized  as  an  essential,  but  it  will 
be  subservient  to  greater  essentials. 


THE    INSERTION    OF    AMALGAM    FILLINGS.       101 

With  this  marked  change  of  estimate,  the  insertion  of  amal- 
gam fillings  has  had,  probably,  more  to  do  than  any  other  one 
thing;  no  other  plastic  possesses  the  requisite  characteristics 
for  demonstrating  so  unmistakably  that  in  dentistry,  as  in 
other  professions,  "  knowledge  is  poiver"  This  arises  from  the 
fact  that,  though  skill  is  required  in  the  working  of  amalgam, 
and  though  skill  does  amply  make  its  mark,  it  is  nevertheless 
possible  to  do  tooth-saving  icorl:  with  it  far  more  easily  than 
with  gold.  From  this  reason  it  is  not  needful  that  the  energy 
of  the  student  be  so  exhaustively  expended  in  the  direction  of 
finger  education  ;  nor  is  the  list  of  those  who  are  capacitated 
for  rendering  truly  creditable  and  compensating  service,  neces- 
sarily, nearly  so  circumscribed.  This  insures  a  wider  latitude 
of  benefit  to  those  who  suffer,  and,  inversely,  it  must  redound 
to  the  elevation  of  dentistry  upon  the  broad  ground  of  great- 
est honor  to  that  which  gives  the  greatest  good  to  the  greatest 
number. 

It  seems  proper  to  prelude  the  directions  for  the  insertion  of 
amalgam  fillings  with  certain  remarks  discussive  of  the  con- 
dition of  cavities  preparatory  to  their  introduction.  In  order 
that  this  shall  be  complete,  it  must  first  be  stated  that  "  excel- 
lent "  amalgam  is  at  present  divided  into  five  kinds  — "  sub- 
marine," "usual,"  "contouring,"  "front  tooth,"  and  "facing." 
Much  effort  has  already  been  expended  for  the  production  of  a 
"  universal  "  alloy ;  but,  as  yet,  I  have  never  seen  any  which 
made  amalgam  that  met  all  indications.  It  appears  to  be  as  im- 
possible to  make  such  an  alloy  as  it  is  to  make  a  form  of  gold 
which  will  prove  equally  acceptable  in  all  cases. 

The  old-fashioned  silver  coin  amalgam  might  be  regarded  as 
the  typal  "submarine,"  for,  although  no  one  would  be  likely 
ever  to  use  it,  it  is  nevertheless  the  basal  idea  for  permanence 
in  submarine  work.  It  has  been  noticed  that  the  blade  amal- 
gam fillings  done  forty  years  ago  have  saved  the  worthless 
shells  in  which  they  were  introduced — -possibly  by  the  finger 
of  some  operator  —  merely  as  experiments,  until,  in  some  cases, 
every  other  tooth  has  passed  away. 

Analysis  of  these  fillings  shows  them  to  be  composed  of 
about  50  parts  mercury,  45  parts  silver,  and  5  parts  copper  — 
approximately ;  and  it  is  from  this  start-point,  then,  that  we 


102  PLASTICS    AND     PLASTIC    FILLING. 

work  for  tooth-conservation  as  a  distinguishing  characteristic  of 
amalgam. 

It  has  also  been  noted  that  the  most  remarkable  instances  of 
long  maintenance  of  integrity  at  the  "  vulnerable  spot " —  cer- 
vical edge  —  and  that,  too,  under  most  disadvantageous  circum- 
stances—  frail  walls,  soft  structure,  beneath  gum,  under  moist- 
ure—  have  been  attained  by  these  black  fillings.  These, 
therefore,  form  the  basis  for  amalgam  intended  for  "  sub- 
marine "  work  in  difficult  and  inaccessible  places. 

/I  have  stated  that  the  thorough  amalgamating  of  coin 
filings  is  a  protracted  and  difficult  piece  of  work ;  also  that 
tin  is  a  notable  facilitator  of  fusion.  It  has  therefore  been 
deemed  advisable  to  add  this  metal,  in  small  quantity  —  from 
80  to  35  per  cent. —  to  alloy,  and  to  substitute  a  portion  of 
grain  silver  —  about  one-third  —  instead  of  using  all  coin.  This 
/makes  a  "submarine" — 60  silver,  35  tin,  5  copper; — the  only 
/positively  determined  alloy  which  practically  meets  the  average 
of  combined  requirements  better  than  coin  amalgam,  and  an 
experience  of  more  than  ten  years  gives  to  it  remarkable 
"  tooth-conservation  "  even  under  extremely  unpropitious  cir- 
cumstances. It  discolors  reasonably  and  with  desirable  prompt- 
ness, if  exigencies  demand  it,  but  does  not,  except  in  rare  in- 
stances, become  as  black  as  coin  amalgam,  and  does  not  impart 
to  the  tooth  that  greenish  hue  so  distinctive  of  copper  in  quan- 
tity, uncontrolled. 

Amalgam  made  from  alloys  of  this  nature  may  be  success- 
fully worked  in  cavities  from  which  it  is  impossible  to  exclude 
moisture.  It  can  be  worked,  and  with  reasonably  good  results, 
—  the  best,  I  think,  which  can  be  made  with  anything, —  in  cav- 
ities which  are  filled  with  moisture ;  but  in  such  I  prefer  that 
the  moisture  shall  be  pure  water,  in  which  is  dissolved  suffi- 
cient carbonate  of  soda  to  render  it  slightly  alkaline,  rather 
than  the  fluids  of  the  mouth,  even  though  these  be  largely 
Composed  of  the  free  Rowing  outpouring  of  the  subliugual  and 
parotid  glands. 

For  this  reason,  I  guard,  as  best  as  I  can,  with  napkins,  against 
flow  of  saliva ;  have  the  cavity  prepared  and  filled  with  cot- 
ton ;  make  ready,  with  decided  plasticity,  my  "  submarine ;  "  fill 
my  syringe  partially  with  the  alkaline  solution,  tepid ;  with- 


THE    INSERTION    OF    AMALGAM     FILLINGS.       103 

draw  the  cotton;  deluge  my  cavity,  and  quickly  place  in  posi- 
tion and  compactly  insert  my  filling  material. 

The  second  kind  of  amalgam  is  that  employed  for  "  usual  " 
work  —  submarine,  one  part ;  contour,  two  parts.  All  alloys 
based  upon  the  "60  silver,  40  tin,"  modified  by  additions  of 
gold  and  copper,  would  naturally  come  into  this  class.  They 
work  with  nice  plasticity;  set  well;  shrink  but  little,  if  any: 
have  sufficient  edge-strength ;  hold  their  color  well,  and  offer 
these  varied  desirable  attributes  in  compensation  for  certain 
loss  of  "  tooth-conservation "  which,  in  usual  work,  is  not  so 
imperatively  demanded. 

In  working  this  amalgam  —  uncombined  with  other  plastics 
—  it  is  undoubtedly  true  that  just  in  proportion  to  the  absolute 
dryness  of  the  cavity,  and  to  the  maintenance  of  dryness  during 
the  thirty  minutes  required  for  "  setting,"  other  things  being 
equal,  will  be  the  perfection  and  durability  of  the  filling.  In 
these  cases,  then,  the  plastic-filler  uses  the  rubber  dam  when 
other  appliances  will  not  insure  sufficient  dryness. 

It  will  be  noted  that  this  use  of  the  dam  takes  from  it  all 
its  horrors,  and  much  that  is  no  more  than  disagreeable,  for 
there  is  never  any  need  for  passing  rubber  or  ligatures  belo\\- 
the  gum,  and,  if  a  clamp  is  occasionally  employed,  its  placing 
and  necessary  strength  of  grip  are,  neither  of  them,  such  as 
would  prove  inflictive,  even  to  a  child. 

The  third  kind  of  amalgam  is  that  especially  intended  for 
contouring  —  approximately,  silver,  58;  tin,  37;  gold,  5.  The 
alloys  which  make  this  are  those  in  which  quick-setting,  ex- 
ceeding edge-strength,  good  color,  and  plasticity  of  working 
are  the  characteristics  which  it  is  the  endeavor  to  secure.  In 
these,  the  copper  is  excluded,  the  quantity  of  gold  increased, 
and  platinum  ignored. 

This  is  the  field  for  present  work  in  connection  with  amal 
gam.  It  must  certainly  be  recognized  that,  in  the  direction 
of  submarine  and  ordinary  work,  the  labors  of  the  "  New  De- 
parture Corps  "  have  been  such  as  to  place  the  composition  of 
future  alloys  upon  a  definite  basis,  which  essentially  differs 
from  that  almost  universally  adopted,  and  which  decidedly  sus- 
tains the  direction  in  which  had  been  developed  the  Lawrence 
and  Hardman  alloys.  I  think  that  the  "  Standard"  alloy  offers 


104:  PLASTICS    AND    PLASTIC    FILLING. 

the  nearest  approximate  to  the  average  of  all  requirements  in 
usual  and  contour  work  that  has  vet  been  attained.  The 
"quality  test"  is  a  touchstone  which,  I  believe,  will  soou  serve 
to  weed  out  inferior  and  injurious  alloys,  and  compel  their  re- 
placement by  those  which  are,  at  least,  much  better;  and  still 
the  model  alloy  for  contouring  is  not  yet  attained. 

Work  is  constantly  being  done  in  this  direction :  a  work 
based  upon  those  data  which,  from  previous  work,  I  have  been 
enabled  to  present  to  the  profession ;  a  work  which  can  be  taken 
up  by  all  investigators  and  experimenters  at  this  point,  with 
the  assurance  that  the  old  landmarks  have  not  been  removed 
without  long  and  careful  consideration,  and  that  the  new  ones 
have  not  been  set  up  until  they  had  been  subjected  to  much 
thought,  scientific  scrutiny,  and  experimental  observation. 

The  fourth  kind  of  amalgam  —  contour,  1  part ;  facing,  2 
parts  —  is  that  used  for  filling  soft  front  teeth  which  have  been 
41  disked  out "  or  "  separated  "  in  such  manner  as  to  preclude 
the  use  of  gutta-percha,  and  in  which  the  cavities  are  either 
too  small  or  are  of  such  shape  and  position  as  to  interfere  with 
advantageous  "  lining." 

These  alloys  of  tin,  silver,  gold,  and  zinc,  while  they  possess 
the  requisites  of  very  good  maintenance  of  color  and  of  non- 
shrinkage,  are  rather  slow  setters  and  deficient  in  edge-strength ; 
but  they  very  well  fill  the  niche  for  which  they  are  intended, 
and  seem  to  complete  the  list  of  means  which  enable  the  plas- 
tic-filler to  enter  into  such  eminently  successful  competition 
with  the  gold-filler  in  the  work  of  saving  the  front  teeth. 

The  fifth  kind  of  amalgam  "facing"  —  approximately,  tin,  50 
odd;  silver,  30  odd;  gold,  5  to  7;  zinc,  2  to  4  —  is  that  which 
at  present  is  least  liable  to  discoloration.  Its  attributes  are  en- 
tirely in  the  direction  of  subserviency  to  its  special  require- 
ments. Moderate  in  its  setting ;  deficient  in  density  ;  wanting 
in  edge-strength,  it  yet  subserves  its  purpose  nicely ;  and  in  a 
very  large  majority  of  cases  enables  the  plastic-filler  to  make 
operations  —  which  would  otherwise  be  unsightly  —  not  only 
acceptable,  but  frequently  so  natural  in  their  appearance  as  not 
to  be  noticeable. 

NOTE.  —  It  will  be  observed  that  by  three  basal  alloys,  and  by  "mixing"  so 
AS  to  make  other  two,  a  complete  succession  of  amalgams  from  "submarine"  to 


THE    INSERTION    OF    AMALGAM     FILLINGS.       105 

'"facing"  are  available,  and  this  without  the  conjoining  of  copper  and  zinc  in 
any  one  of  them. 

Amalgam  mass,  having  been  made  ready  for  insertion,  is 
held  in  the  palm  of  the  non-operating  hand  by  the  closed  fourth 
and  little  fingers.  The  palm  being  turned  up  and  the  ringers 
raised  from  the  button,  a  portion  of  amalgam  is  cut  off  by  the 
thumb-pliers  and  is  taken  by  them  and  —  the  button  being 
again  covered  —  placed  in  the  cavity.  If  this  be  in  a  lower 
tooth,  the  piece  will  naturally  lie  in  position ;  but  if  it  be  an 
upper  tooth,  the  piece  will  have  to  be  retained  in  place  by  one 
of  the  free  fingers  of  the  hand  containing  the  button. 

The  piece  should  now  be  crushed  by  one  of  the  round-end  or 
flat-end  pluggers,  and  thus  secured  in  position ;  it  must  then  be 
tapped  with  light  blows  from  an  appropriate  instrument  until  it 
is  placed  in  accurate  apposition  with  the  walls  of  the  cavity. 
It  has  long  been  the  practice  to  rub  amalgam  into  contact  with 
•cavity-walls,  and  to  rub  the  various  pieces  consecutively  into 
union  with  the  amalgam  already  introduced,  but  the  filling  of 
the  lower  part  of  two  small  glass  vials  will  easily  convince  anv 
one  of  the  decided  superiority  of  "  tapping  "  over  "  rubbing." 
A  piece  of  paper  should  be  pasted  around  that  portion  of  each 
vial  which  is  to  be  filled.  This  prevents  watching  the  prog- 
ress of  the  filling  and  renders  the  vial,  in  this  respect,  more 
like  unto  a  tooth.  Then  fill  one  vial  very  thoroughly  and  very 
carefully,  taking  extra  pains,  by  the  rubbing  and  burnishing 
method.  Then  fill  the  other,  with  only  ordinary  care,  by  tap- 
ping the  pieces  into  position  and  into  homogeneity  the  one  with 
the  other.  Scrape  off  the  paper,  and  it  is  quite  probable  that 
the  most  skeptical  will  be  entirely  convinced  as  to  which  is  the 
better  method. 

It  has  been  stated  that  amalgam  should  be  malleted,  either 
by  hand  or  automatic  mallet.  I  regard  this  as  not  only  unneces- 
sary, but  really  objectionable.  It  is  not  needful  that  the  blows 
should  be  in  any  degree  forcible,  but,  on  the  contrary,  it  is  better 
that  they  should  be  such  as  would  more  properly  come  under 
the  signification  of  "taps."  The  consistency  of  the  amalgam 
should  be  such  as  will  permit  of  perfect  adaptation  of  filling 
to  cavity-wall  by  tapping  with  light  blows. 

In  the  same  manner  as  is  cut  off  and  introduced  the  first 


106  PLASTICS    AND    PLASTIC    FILLING. 

piece,  so  should  the  succeeding  pieces  be  cut  off'  and  introduced, 
each  piece  being  united  to  its  predecessors  by  tapping ;  without 
this  precaution,  the  unions  are  imperfect,  lines  of  demarcation 
between  pieces  are  clearly  apparent,  and  leakage  is  inevitable. 

The  mass  should  work  quite  plastic  —  generally  becoming 
more  and  more  so  as  the  filling  progresses  —  until  the  cavity,  if 
it  be  of  ordinary  size,  is  completely  filled,  when  a  "last  piece  " 
should  be  enveloped  in  a  fold  of  chamois  skin  and  squeezed 
hard,  and  the  wafer  thus  made  be  laid  on  the  filling.  By  crush- 
ing this  wafer  into  powdery  pieces  and  tapping  these  into  homo- 
geneity with  the  softer  mass,  the  setting  will  be  hastened,  and 
the  edg3-strength,  density,  and  whiteness  of  the  filling  are  much 
increased. 

This  process  is  called  "wafering,"  and  will  be  discussed  in 
the  article  on  "  Technicals  of  Plastic  Filling."  I  have  said  that 
if  the  cavity  be  of  ordinary  size,  the  process  of  wafering  should 
be  used  after  the  cavity  is  completely  filled ;  this  is  so  because 
the  size  of  the  filling  is  not  so  great  as  to  prevent  a  sufficient 
effect  upon  the  whole  mass  from  one  wafering ;  but  if  the  cavity 
is  very  large,  or  if  it  is  inaccessible,  it  is  better  that  two  or 
three  mixings  be  made,  in  small  quantity,  and  that  each  mix 
be  hardened  and  set  by  its  own  wafer.  This  will  be  found  par- 
ticularly advantageous  in  "  building "  crowns,  or  in  making- 
large  reparations,  as  contouring  amalgam  may  be  so  worked  by 
this  treatment  as  to  set  almost  as  fast  as  it  is  built  on,  and  to 
become  sufficiently  hardened  in  an  hour  or  two  to  subserve  the 
purposes  of  mastication  or  of  clasping. 

After  the  filling  is  wafered,  it  should  be  shaped  by  trimming, 
or,  if'  not  .too  hard,  it  may  be  smoothed  into  shape  by  a  piece 
of  soft  pine  stick.  For  this  purpose,  I  have  pieces  of  white 
pine  —  the  softest,  and  of  perfectly  straight  grain  —  prepared 
in  slips  of  six  inches  long,  three-eighths  wide,  and  three-six- 
teenths thick ;  the  ends  of  some  are  cut  to  a  small  round  for 
articulating  faces,  and  the  ends  of  others  are  cut  to  a  delicate 
chisel  shape  for  smoothing  buccal  surfaces  and  for  finishing 
between  teeth.  Smaller  pieces  are  adapted  to  a  Cogswell,  or 
other  wood  carrier,  and  are  thus  used  in  inaccessible  places. 

After  the  filling  is  smoothed,  it  should  be  allowed  to  harden 
for  ten  or  fifteen  minutes;  it  should  then  be  burnished,  and 


GENERAL    CONSIDERATIONS.  107 

smoothed  aerain  with  the  stick:  then  allowed  to  harden  for  an- 

o 

other  ten  minutes,  when  it  should  be  finally  burnished  and 
finished  white  with  the  piece  of  stick,  using,  if  necessary,  a  little 
very  finely  levigated  pumice.  In  smoothing  for  final  finishing, 
the  stick  should  be  passed  over  the  face  of  the  filling  up  or 
down  and  not  across  the  filling  ;  this  leaves  the  lines  of  finish  so 
that  the  light  will  strike  upon  presenting  parallel  faces,  and 
thus  gives  to  the  filling  a  much  whiter  appearance. 

In  such  amalgams  as  are  controlled  by  copper  and  gold,  this 
face  will  frequently  be  very  well  maintained,  and  I  therefore 
think  it  advisable  to  permit  the  opportunity  for  their  doing  so, 
but  if  the  filling  should  discolor,  it  can  at  any  subsequent  time 
be  filed  or  burred  off',  smoothed  and  burnished.  Such  amalgam 
fillings  will,  almost  universally,  retain  the  brightness  of  this 
burnished  face. 

It  has  been  sometimes  directed  to  burnish  the  edges  of  amal- 
gam fillings  after  they  have  assumed  a  partial  hardness.  I  can 
only  regard  this  practice  as  beneficial  with  the  very  poorest 
amalgams,  such  as  shrink  notably,  have  but  little  edge-strength, 
and  crevice  markedly;  but  I  should  equally  regard  it  as  posi- 
tively detrimental  to  a  filling  of  good  amalgam,  and  detrimental 
just  in  proportion  to  the  excellence  of  the  amalgam.  A  filling 
made  of  excellent  amalgam  should  have  a  clean,  sharp  edge, 
of  great  strength,  which  should  never  be  broken  by  burnishing, 
but,  on  the  contrary,  should  be  allowed  to  harden  thoroughly, 
and  depend  upon  its  own  physical  characteristics  for  its  integrity. 


ARTICLE   XII. 

GENERAL   CONSIDERATIONS  PERTAINING   TO 

AMALGAM. 

TN  taking  up  this  subject  under  the  three  divisions  of:  1.  Lo- 
-L  cal  effects;  2.  Systemic  effects;  3.  Possibilities,  I  cannot 
help  premising  that,  from  my  standpoint  of  observation  and 
experience,  the  outlook  is  something  so  novel  to  the  typal  den- 
tist of  the  golden  age  as  to  appear  absurd,  and,  even  more  than, 
this,  wild  and  visionary ;  but  I  am  quite  sure  that  to  the 
younger  men,  those  who  have  inherited  the  leavings  of  the 


108  PLASTICS    AND     PLASTIC    FILLING. 

past  half  century's  efforts  at  saving  (?)  teeth,  those  who  have 
to  grapple  with  the  daily  task  of  overcoming  such  apparent 
impossibilities  as  would  not  even  be  attempted  by  the  most 
enthusiastic  workers  in  gold  more  frequently  than  once  a 
week,  and,  more  than  this,  to  antagonize  and  conquer  presen- 
tations that  would  be  utterly  hopeless  in  usual  practice,  or  else 
continue  in  the  wholesale  extraction  of  the  present,  and  help 
to  flood  the  nations  with  artificial  dentures,  my  views  of  amal- 
gam will,  at  least,  seem  worthy  of  perusal  and  of  thought, 
and  that  it  will  be  recognized  by  them  that  what  has  been 
done  so  satisfactorily  as  to  have  engendered  such  opinions, 
might  well  be  tried  in  vastly  more  extended  fashion,  and  with 
the  determination  to  give  to  the  experimentation  the  benefit 
of  every  doubt. 

I  feel  strongly  the  truth  of  the  position  that  amalgam  has 
been  so  long  decried,  and  is  so  very  meritorious,  that  I  may 
be  pardoned  for  urging  its  claim  with  evident  partisanship.  I 
feel  that  in  doing  this  I  cannot  do  the  thousandth  part  of  the 
great  wrong  to  humanity  which  has  been  done  by  those  who 
have,  for  many  years,  so  successfully  debased  it  to  a  low  posi- 
tion. I  feel  that  it  has  been  used  by  the  very  men  that  have 
abused  it,  when  they  could  use  nothing  else,  and,  that  when  it 
has  responded  to  their  call  most  grandly,  they  have  ranked  it 
as  secondary  the  more  decidedly,  from  very  fear  that  its  facts 
might  supplant  their  theories. 

This  is  strong  placing ;  but  it  is  none  too  strong ;  for,  by 
this  doctrine  of  subordination  of  this  valuable  material,  by  this 
teaching  that  in  its  requirement  of  little  skill,  and  in  its  glori- 
ous attribute  of  easy  working,  it  lowered  its  manipulator  and 
degraded  dentistry,  thousands  of  dentists  have  been  restrained 
from  using  it  when  it  would  have  been  the  very  best  thing 
known  for  the  requirements,  and  have  been  stimulated  to  the 
employment  of  gold  in  cases  where  it  has  constantly  exhibited 
the  most  signal  lines  of  failure  even  when  worked  by  the  few 
who  were  dignified  by  the  ranking  of  "  eminently  skilful." 

Tens  of  thousands  of  cavities  have  been  thus  filled  at  fear- 
ful expenditure  of  time,  suffering,  and  expense,  which  ouyht  to 
have  been  quickly,  comfortably,  and  economically  filled  with 
amalgam. 


GENERAL,    CONSIDERATIONS.  109 

Hundreds  of  thousands  of  teeth  have  been  lost,  years  before 
their  time,  from  no  other  cause  than  that,  in  using  gold,  impos- 
sibilities were  attempted  in  defiance  of  incompatibility  of  ma- 
terial, and  in  despite  of  the  insurmountable  physical  character- 
istics which  precluded  its  working ;  while,  with  amalgam,  these 
years  of  comfort  could  have  been  bestowed  through  its  nearer 
approach  to  compatibility,  its  peculiar  tooth-saving  property 
of  forming  soluble  sulphides,  and  the  physical  characteristics 
which  permit  its  easy  working  under  most  disadvantageous 
circumstances,  and  in  most  inaccessible  cavities. 

Through  the  dogmas  of  the  superiority  of  gold  as  a  filling 
material  and  the  elevating  of  its  working  to  the  position  of 
"  standard  for  excellence,"  and  of  the  inferiority  of  amalgam 
as  a  filling  material  and  the  degrading  of  its  working  to  the 
position  of  "  standard  for  incapacity,"  millions  of  teeth  have 
been  needlessly  sacrificed,  and  their  places  filled  with  those 
cunning  devices  of  quartz,  feldspar,  and  kaolin  which  are  so 
appropriately  designated  —  substitutes. 

My  voice  is  given  in  antagonism  to  such  teaching  and  to 
such  practice  with  full  confidence,  born  of  years  of  severe 
testing,  that  a  change  cannot,  by  any  possibility,  produce  any 
more  discreditable  results ;  and  with  a  firm  hope  that  it  may 
give  comfort,  health,  and  teeth  to  those  whose  fathers  and 
mothers  have  lost  all  these  at  the  hands  of  first-class  accepted 
dentistry. 

1.  Local  effects. —  As  I  have  intimated,  in  previous  articles, 
the  local  effects  of  amalgam  are  not  altogether  what  we  would 
desire  ;  but,  as  I  have  also  stated,  most  emphatically,  they  are 
in  great  degree  eminently  desirable.  It  therefore  behooves 
us  to  discuss,  clearly  and  dispassionately,  this  important  matter 
in  its  perfectly  tangible  bearings. 

I  desire  that  it  shall  be  understood  that  I  regard  it  as  need- 
less now  to  discuss,  at  any  length,  the  peculiarities  pertaining 
to  ordinary  amalgams;  for  it  is  a  principal  object  with  me  to 
give  such  information  regarding  "  plastics "  as  shall  force  all 
ordinary  materials  from  the  market,  unless  they  are  offered  as 
such. 

While  this  arrangement  will  exclude  the  vast  majority  of 
amalgam  alloys  at  present  manufactured  and  used,  it  will  yet 


110  PLASTICS    AND    PLASTIC    FILLING. 

permit  the  retention  of  some  that  are  worthy  of  limited  con- 
tinuance, at  least  until  they  are  replaced  by  various  makes 
which  shall  possess  generally  good  characteristics. 

But  it  will  also  permit  the  retention  of  some  which  are  given 
as  possessing  the  very  objectionable  distinguishing  characteris- 
tic of  decided  tendency  to  discoloration.  This  peculiarity,  then, 
must  be  accepted,  with  its  concomitant  tooth  discoloration,  at  its 
precise  valuation  ;  it  must  be  viewed  as  unfortunate  that  we 
have  not  yet  attained  any  non-discoloring  amalgam  which 
we  can  positively  declare  to  be  as  tooth-saving  as  those  which 
freely  discolor ;  but  it  must  also  be  taken  as  partial  compensa- 
tion for  this,  that  we  have  succeeded  in  establishing  the  remark- 
able control  exercised  by  zinc  and  gold  over  this  discoloration, 
and  that  such  amalgams  are  notably  creditable  as  tooth-savers. 

It  must  be  recognized  that  if  an  amalgam  which  discolors - 
as,  for  instance,  made  from  alloy  of  silver  60,  tin  35,  copper  5  — 
is  chosen  as  a  filling  material,  its  local  effects  are  regarded  as 
such  as  overbalance  in  good  that  which  is  admitted  as  bad.  It 
works  plastic  against  frail  walls;  it  works  as  a  submarine;  it 
sets  with  desirable  celerity ;  its  shrinkage  is  infi  nitesimal ;  its 
edge-strength  is  good.  All  these  are,  indisputably,  desirable 
qualities ;  but  it  permits  the  formation  of  sulphides,  and  in  so 
doing  produces  two  results  —  the  filling  becomes  darkened  and 
presents  an  unsightly  appearance,  and  the  tooth  assumes  a  dark- 
ish hue,  sometimes  even  blue-black,  which  is  also  eminently 
disagreeable  to  view.  But,  again,  this  very  process  is  the  saving 
of  the  tooth,  and  it  therefore  becomes  simply  a  question  of  util- 
ity vs.  beauty,  which,  it  seems  to  me,  could  in  every  instance 
very  readily  be  promptly  and  satisfactorily  settled  between  pa- 
tient and  operator  by  a  plain  presentation  of  facts. 

Another  local  effect  is  the  occasional  induction  of  galvanic 
electricity  ly  contact  with  other  metal.  This  is  most  usually  de- 
veloped when  such  contact  is  made  .by  touching  fillings  with 
pins,  needles,  metallic  toothpicks  or  forks, —  either  steel  or  sil- 
ver,—  and  the  results  vary  in  degree  from  merely  making  a 
peculiar  taste,  galvanic,  through  the  entire  range  of  sensation 
from  disagreeable  to  intensely  painful  —  a  shock. 

AVhen  this  occurs,  the  filling  should  be  removed  and  an  in- 
sulating medium  —  either  zinc-sulphate,  varnish,  oxy-chloride, 


GENERAL    CONSIDERATIONS.  Ill 

gutta-percha,  arnica  court-plaster  (water-proof),  or  any  equiva- 
lent to  these  —  should  be  so  placed  as  to  cut  off  the  sentient 
conductivity,  and  thus  preclude  such  liability. 

This  effect  is  quite  liable  to  be  produced  from  contact  with 
the  clasps  or  plate  of  artificial  dentures  —  gold  —  and  is  some- 
times, though  rarely,  difficult  of  prevention.  ]t  is  in  some 
cases  readily  obviated  by  so  filing  the  plate  as  to  preclude  its 
touching  the  filling  during  the  insertion  or  removal  of  the  work 
and  during  mastication. 

If  the  unpleasant  effect  is  due  to  contact  of  clasp  with  fill- 
ing—  either  in  clasp  teeth  or  adjoining  teeth  —  the  means  for 
prevention  are  more  complex,  less  positive,  and  require  more 
careful  consideration.  Regarding  difference  in  potential  and 
brightness  of  metallic  surface  as  the  combining  circumstances 
which,  under  peculiar  condition  of  oral  fluids,  produce  this  re- 
sult, the  first  effort  should  be  the  removal  of  brightness. 

This  is  done  by  oxidizing  the  clasp  by  heat,  and  by  "  facing" 
the  bright-surfaced  amalgam  with  a  thin  layer  of  "submarine," 
mixing  a  small  pellet  of  this  kind  of  amalgam  and  rubbing  it 
on  those  faces  of  the  filling  which  are  touched  by  the  clasp, 
and  then  removing  it  to  original  contour  as  the  thinnest  possi- 
ble film  is  sufficient ;  or,  by  coating  the  inside  of  the  clasp  with 
a  mercurial  covering  by  rubbing  upon  it  a  small  portion  of 
amalgam,  which  if  done  carefully,  so  as  to  impinge  upon  no 
part  of  the  work  except  the  inner  portion  of  the  clasp,  will 
not  spread,  neither  will  it  enter  into  the  substance  of  the  clasp 
sufficiently  to  be  detrimental ;  or,  by  changing  the  location  of 
the  clasp  and  securing  to  another  tooth ;  or,  by  using  silver  for  a 
clasp,  leaving  it  darkened  from  the  blow-pipe;  or,  by  changing, 
if  possible,  the  filling  material  to  some  other,  though  less  relia- 
ble and  less  durable  plastic;  or,  as  a  final  resort,  if  "clasping" 
is  a  necessity  or  a  very  great  comfort,  the  devitalization  of  the 
pulp  of  the  clasp-tooth. 

This  latter  consideration  is  one  which  it  is  supposed  will 
be  subject  to  that  recognition  of  contingencies — probabilities 
and  possibilities  pertaining  to  pulpless  teeth — which,  with  the 
knowledge  of  the  present  day,  are  so  accurately  reduced  to 
debatable  propositions.  In  mouths  where  this  galvano-elec- 
tric  effect  is  very  decided,  it  will  occasionally  be  noted  that  the 


112  PLASTICS    AND     PLASTIC    FILLING. 

contact  of  small  pieces  of  amalgam  with  gold  fillings  will  pro- 
duce a  like 'effect.  Thus,  the  dropping  of  debris  during  the 
introduction  of  amalgam  fillings,  or  the  making  of  contact 
during  the  rinsing  of  the  particles  from  the  mouth,  will  oc- 
casion more  or  less  decided  starting  on  the  part  of  the  patient, 
and  will  require  the  desired  explanation.  In  filling  under 
rubber-dam,  this  difficulty  would,  of  course,  not  occur ;  but  in 
napkin  filling,  the  napkin  should  be  so  arranged  as  to  secure,  if 
possible,  the  catching  of  all  dropping  filling  material. 

A  third  effect  is  like  unto  this  second,  but  is  occasioned  from 
the  fact  that  a  filling  of  different  metal,  having  marked  differ- 
ence of  potentiality  (usually  gold},  is  so  inserted — disconnected, 
not  touching — into  the  same  tooth  or  an  adjoining  tooth  as  to  be  oc- 
casionally connected  by  tongue,  lip,  or  cheek  connection.  When- 
ever this  connection  is  made  —  usually  during  mastication  —  a 
shock  of  sufficient  severity  to  cause  pain  and  starting  is  felt. 
This  is  cured,  either  by  thoroughly  amalgamating  the  face  of 
the  gold  filling,  or,  if  in  one  tooth,  by  cutting  away  between  the 
two  fillings  and  making  them  join,  using  either  amalgam  or  gold 
for  this  purpose,  as  is  indicated  either  from  considerations  of 
appearance  or  ease  of  manipulation  ;  if  it  arises  from  fillings  in 
two  teeth,  one  of  the  two  fillings  may  be  removed  and  replaced 
with  a  like  material  to  the  remaining  filling.  I  should,  of 
course,  advocate  the  removal  of  the  gold  filling  and  its  replace- 
ment either  with  tin,  gutta-percha,  or  amalgam,  according  to 
circumstances,  as  I  should  suppose  the  considerations  which 
prompted  the  introduction  of  amalgam  in  one  of  the  cavities 
would  outweigh  the  objections  which  might  pertain  to  the  use 
of  one  of  the  other  materials  mentioned.  It  will  be  noted  that 
effects  like  these  could  only  occur  in  wholly  vital  teeth. 

A  fourth  effect  is  a  species  of  metallic  salivation  due  to  action 
through  the  "gustatory"  reflected  through  the  "nutrient"  of 
the  salivary  glands.  This  is  a  very  rare  occurrence,  though  I 
have  met  with  a  few  cases  of  it.  I  have  always  classed  it  as 
physiological  rather  than  pathological  action,  and  regarded  it 
as  similar  to  the  effects  occasionally  produced  through  the 
optic  and  auditory  nerves  at  the  sight  or  mention  of  certain 
kinds  of  food.  This  effect  is  sometimes  of  but  short  duration 
—  a  few  days  —  and,  as  the  faces  of  fillings  lose  their  bright- 
ness, it  gradually  passes  away.  Having  noticed  this,  I  act 


GENERAL    CONSIDERATIONS.  113 

upon  the  hint,  and  in  cases  where  it  is  persistent,  and  in  which 
the  faces  of  fillings  maintain  good  color  markedly,  I  remove 
them  and  replace  with  amalgam  which  discolors,  carefully 
lining  the  cavities  so  as  to  prevent  tooth  discoloration. 

A  fifth  effect  is  that  of  giving  rise  to  a  bad  taste  •  this  is  even 
more  rare  than  the  preceding  one,  and  does  not  occur  more  fre- 
quently than  once  in  from  five  hundred  to  eight  hundred 
mouths.  In  every  instance,  except  one,  which  I  have  seen  of" 
this  condition,  the  teeth  were  of  that  kind  in  which  gold  had 
been  tried  by  various  operators  of  acknowledged  skill,  with 
anything  but  satisfactory  results,  and  in  the  one  exceptional 
case  I  heard  that  a  most  extensive  and  elaborate  line  of  gold 
work  was  finally  resorted  to.  In  these  cases  I  have  removed 
the  amalgam  and  resorted  to  gutta-percha,  oxy-chloride  of  zinc, 
and  zinc-phosphate  fillings  with  the  requisite  renewals. 

A  sixth  effect  is  an  irritation  of  the  fauces,  throat,  and  larynx, 
which,  while  it  is  not  primarily  dependent  upon  the  presence 
of  amalgam,  is  nevertheless  much  less  amenable  to  treatment, 
while  numbers  of  large  amalgam  fillings  are  in  the  mouth.  In 
an  amalgam  practice  of  twenty -five  years,  and  with  an  experi- 
ence in  more  than  five  thousand  mouths,  I  have  met  with  but 
two  cases  of  this  kind.  In  both  these  cases  serious  bronchial 
trouble  was  previously  constantly  existent,  but  was  decidedly 
less  controllable  under  amalgam  irritation  than  without  it. 

In  both  these  cases  I  removed  the  amalgam  and  refilled  with 
gutta-percha  and  oxy-chloride,  and,  more  recently,  with  zinc- 
phosphate,  and  in  both  instances  with  relief  to  the  patient. 

It  is  more  than  probable  that  the  vast  majority  of  prac- 
titioners would  pass  an  entire  lifetime  without  meeting  any 
such  cases  as  these  I  have  last  referred  to,  but  it  is  well  to 
know  that  idiosyncrasies  exist  in  which  such  things  can  occur, 
in  order  that  one  may  be  prepared  to  meet  them  should  they 
happen  to  present  themselves. 

As  for  the  other  local  effects,  which  are  frequently  charged 
to  amalgam,  such  as  pulp-devitalization,  periodontitis,  alveolar 
abscess,  exostosis,  and  necrosis,  I  must  say,  most  decidedly, 
that  I  have  never  met  with  an  instance  in  which  any  of  these 
conditions  existed  with  amalgam  fillings  as  concomitants,  and 
in  which  I  could  not  think  that  it  would  probably  have  oc- 


114  PLASTICS    AND     PLASTIC    FILLING. 

curred,  under  similar  circumstances,  in  connection  with  any 
other  metallic  filling  material. 

2.  Systemic  Effects. —  I  have  already  spoken  of  the  discus- 
sions which  I  asked  from  the  Pennsylvania  Association  of 
Dental  Surgeons  almost  twenty  years  ago.  It  may  be  sup- 
posed that,  as  I  had  been  for  six  years  directing  close  attention 
to  all  such  matters  as  could  be  pretty  well  settled  in  that  space 
of  time,  I  would  have  especial  interest  in  the  views  of  my 
fellow-members  upon  a  subject  of  such  grave  moment,  and 
of  such  difficulty  in  establishing  data  ly  one  observer,  as  that  of 
the  systemic  effects  of  amalgam  fillings. 

I  had  already  conversed  with  many  of  the  elders  of  den- 
tistry, and  had  found  that,  without  exception,  those  who  had 
had  experience,  either  limited  or  extended,  were  alike  positive 
in  the  denial  of  any  such  systemic  effects  as  could  be  attributa- 
ble to  mercurials,  while  I  had  also  found  that  the  few  who  "  be- 
lieved "  in  this  possibility,  were  also,  without  exception,  either 
avowedly  reiterating  the  views  of  those  in  whom  they  had 
confidence,  but  without  having  any  personal  knowledge  in 
relation  to  it,  or  were  openly  hostile  to  its  use,  without  ever 
having  investigated  its  merits  or  demerits  to  the  extent  of  even 
one  filling. 

In  referring  to  the  proceedings  of  the  meeting  of  April,  1861, 
reported  in  "  Cosmos,"  May,  1861,  I  find  that  I  expressed  thus 
early  in  my  work  the  opinion  that,  while  it  was  "  barely  possi- 
ble "  an  idiosyncrasy  could  exist  in  which  amalgam,  per  se. 
might  be  injurious,  it  was,  nevertheless,  a  thing  which  I  had 
never  seen. 

I  quote  briefty  to  show  the  collateral  basis  which  was,  upon 
that  occasion,  given  me,  and  which  I  regarded  as  substantiating 
my  own  opinion  sufficiently  for  all  practical  purposes. 

Dr.  C.  Newlin  Pierce,  who  opened  the  discussion,  said,  in  re- 
gard to  amalgam  ptyalism,  that  it  was  a  thing  of  "  so  rare  an 
occurrence,  that  he  believed  the  profession  had  never  heard  of 
but  one  practitioner  who  thought  that  that  result  was  produced 
by  amalgam." 

Prof.  T.  L.  Buckingham  said  "he  had  never  seen  a  case  of 
salivation  from  its  use,  and  -had  doubts  about  its  ever  having 
produced  ptyalism;1'  that  mercurial  effects  were  "influences 


GENERA  I.    CONSIDERATIONS.  115 

produced  through  the  general  system; 'but  he  did  not  think 
amalgam  fillings  would  produce  these  effects." 

Dr.  J.  H.  McQuillen  said  that  "  in  an  experience  of  fourteen 
years  he  could  not  recall  a  single  instance  of  necrosis  of  the 
jaws,  ptyalism,  etc.,  of  which  others  assert  that  they  have  seen 
so  many;"  and  that  while  he  recognized  the  fact  of  idiosyn- 
crasies in  which  the  smallest  quantity  of  certain  medicinal 
agencies  is  followed  by  untoward  results,  and  would  not,  there- 
fore, offer  his  negative  testimony  as  positive  proof,  yet  "his 
own  experience  had  made  him  look  upon  those  who  assert 
that  they  have  seen  so  many  cases  with  considerable  doubt  as 
to  the  value  of  their  judgment  or  opinions  as  reliable  diagnos- 
ticians." 

Dr.  C.  P.  Fitch  said,  "in  regard  to  its  toxical  or  injurious 
effects  upon  the  system,  he  was  inclined  to  question,  if  not 
wholly  doubt,  any  such  influence,  and  concurred  in  the  views 
advanced  by  Dr.  McQuillen,  that  he  had  yet  to  see  the  first  case 
of  alveolar  abscess,  ptyalism,  etc.,  due  to  the  presence  of  mer- 
eurv  in  the  amalgam." 

Dr.  J.  M.  McGrath  testified  for  himself  and  for  his  father,, 
who  had  had  an  amalgam  experience  of  ten  or  fifteen  years,, 
that  as  yet  they  "had  never  seen  any  bad  effects  resulting,  such. 
as  had  been  ascribed  to  its  use  by  many  practitioners." 

Thus  it  was  that  I  was  fortified  by  the  combined  testimony 
of  gentlemen  whom  I  esteemed  as  conscientious  observers,  and 
for  whom  I  had  much  regard  both  socially  and  professionally. 

It  now  remains  for  me  to  add  the  testimony  of  almost  twenty 
years  more  of  increasingly  acute  scrutiny,  with  the  assertion 
that  during  all  mv  amalgam  experience  I  have  never  seen  one 
case  of  mercurial  ptyalism,  mercurial  periostitis,  mercurial  ne- 
crosis, or  of  the  slightest  symptom  which  could  reasonably  be 
ascribed  to  mercurial  action.  I  have  had  cases  of  asserted  mer- 
curializatioD  by  the  score  brought  to  me.  I  have  treated  them 
experimentally  with  chlorate  of  potassium  to  demonstrate  its 
utter  impotency,  and  have  then  cured  every  case  without  the  use 
of  any  anti-mercurials,  and  have  left  the  teeth  refilled  with 
amalgam.  If  anything  more  convincing  than  this  is  required, 
I  have  it  not  to  offer.  And  yet  the  cry  of  mercurial  ptyalism 
still  continues.  It  is  repeated  not  only  by  medical  men,  for 


116  PLASTICS    AND    PLASTIC    FILLING. 

whom  we  must  have  the  needed  leniency,  but  it  is  stated  boldly 
and  persistently  by  dentists;  by  men  who  have,  at  least,  local 
reputation,  and  are  thereby  capable  of  doing  harm.  But  I  wish 
it  to  be  noted  that  no  man  of  record,  either  scientific,  literary, 
or  professional  —  beyond  the  making  of  a  good  gold  filling  — 
can  be  found  to-day  who  will  commit  himself  by  the  assertion 
that,  from  observation  and  experience,  he  believes  amalgam 
fillings  are  liable  to  produce  mercurial  ptyalism,  and  are,  there- 
fore, unfit  to  use  in  efforts  for  saving  teeth. 

3.  Possibilities. — With  this  theme  I  am  filled  with  such 
thankfulness  at  the  knowledge  of  these,  and  with  such  grati- 
tude that  my  professional  career  has  been  in  the  pathway 
opened  to  me  by  them,  that  I  long  to  tell,  in  one  word,  of  the 
possibilities  of  the  various  amalgams;  it  seems  to  me  as  though 
there  was  but  one  word  which  could  express  it,  and  that  is 
fulness. 

Of  all  the  other  filling  materials,  there  is  no  one  which  cov- 
ers a  tithe  of  the  ground  in  dental  demands  that  is  covered  by 
amalgam  when  used  with  a  knowledge  of  its  possibilities.  Far 
more  than  this,  I  most  unhesitatingly  assert  that,  in  a  practice 
which  shall  save  every  tooth  and  root  that  offers  which  can  be 
saved  advantageously,  amalgam  will  enable  an  operator  to  pro- 
duce more  satisfactory  results  —  grading  these  from  an  average 
of  the  varied  stand-points  of  beauty,  permanency,  comfort,  econ- 
omy, and  utility — than  all  the  other  filling  materials  combined. 

It  may  well  be  regarded  that  I  would  not  make  any  such 
statement  as  this  without  much  consideration ;  and  it  may  well 
be  admitted  that  I  have  had  an  experience  which  has  given  me 
ample  data  upon  which  to  base  an  opinion  ;  and  it  is,  therefore, . 
upon  the  combined  strength  of  reflection,  experiment,  and  ob- 
servation that  I  have  ventured  the  position. 

The  possibilities  of  amalgam ;  it  is  an  easy  thing  to  tell  of 
its  possibilities,  but  its  limits  —  for  it  has  limits  —  are  not  so 
readily  defined.  It  can  take  care  of  almost  anything  in  den- 
tistry; and  it  really  seems  as  though  its  possibilities  were  more 
and  more  demonstrable,  just  in  proportion  as  the  result  desired 
seems  more  and  more  impossible  of  accomplishment.  The  things 
which  are  easy  to  do  with  gold  are  easier  done  with  amalgam. 
The  things  which  are  hard  to  do  with  gold  are  easily  done 


GENERAL    CONSIDERATIONS.  117 

with  amalgam.  The  things  which  are  exceedingly  difficult  to 
do  with  gold  are  not  difficult  to  do  with  amalgam.  The  things 
which  are  almost  impossible  to  do  with  gold  are  not  difficult 
to  do  with  amalgam.  The  things,  by  the  dozen,  which  are  im- 
possible to  do  with  gold  are  not  very  difficult  to  do  with  amal- 
gam. And  to  do  well,  too ;  to  do  in  such  wise  as  that  they 
shall  be  eminently  useful,  durable,  comfortable,  and  satisfac- 
tory; to  do  in  such  wise  as  that  the  recipients  shall,  after  years 
of  trial,  point  to  them  as  proofs  to  others  that  they,  too,  can 
enjoy  such  benefits. 

And  this  is  the  material  that  for  fifty  years  has  been  stigma- 
tized as  base;  frowned  upon  as  low;  tabooed  as  unworthy  the 
notice  of  skilful  men ;  disgraced  as  the  token  of  incapacity  and 
quackery.  Is  it  not  time  that  this  thing  should  be  ended  ?  Is 
it  not  time  that  its  serious  investigation  should  be  undertaken 
by  the  coming  men  of  dentistry  ? 

Ordinary  Cavities. —  It  has,  for  so  long  a  period,  been  regarded 
as  the  proof  of  incompetency  that  an  operator  should  even 
think  of  filling  ordinary  cavities  of  decay  with  anything  but 
gold,  that  I  deem  it  of  exceeding  importance  that  I  should  pre- 
sent this  subdivision  of  my  subject  with  that  precision  and  de- 
cision to  which  I  esteem  it  entitled. 

It  has  been  a  systematic  thing  with  me  to  do  so  for  many 
years,  for  I  was  early  impressed  with  the  fact  that  this  fallacy 
was  probably,  of  all  others,  the  most  pernicious. 

Who  would  think  of  allowing  a  small  break  in  a  dyke  to 
become  an  enormous  crevasse  before  trying  means  for  its  arresta- 
tion  which  had  been  demonstrated  to  be  equal  to  extraordinary 
emergencies. 

Who  would  think  of  allowing  a  small  fire  to  increase  in  size 
until  it  should  demand  the  services  of  a  steam  fire-engine,  if  one 
had  the  engine  in  readiness  to  extinguish  the  flames  in  their 
incipiency  ? 

Who  but  an  old  school  dentist  would  order  that  a  small  cav- 
ity in  a  soft,  young  tooth  should  be  filled  and  refilled  with  gold, 
until,  as  filling  after  filling  dropped  out,  the  decay  had  pro- 
gressed to  such  extent  as  to  render  it  impossible  that  it  could 
be  filled  with  anything  but  amalgam  ? 

And  more  than  this,  who  but  an  old  school  dentist  would 


118  PLASTICS    AND    PLASTIC    FILLING. 

make  obedience  to  this  order  the  test  for  capacity  and  for  "respect- 
ability "  as  a  dentist?  It  is  too  late  for  the  premises  in  these 
questions  to  be  disputed  ;  such  practice  is  not  only  advocated, 
but  it  is  ordered.  Such  results  are  not  problematical ;  they  are 
the  usual,  almost  invariable  results  of  such  practice. 

And  deviation  from  this  rule  has  always  brought  contempt 
upon  the  man  who  deviated,  that  he  might  save  teeth,  from  all 
the  members  who  were  regularly  recognized  as  "  most  respect- 
able." This  has  been  the  tone  of  the  vast  majority  of  practi- 
tioners ;  it  has  been  the  tone  of  the  society  discussions ;  it  has 
been  the  tone  of  the  lecture  stands ;  it  has  been  the  tone  of  the 
journals,  both  small  and  great  —  and  thus  it  has  been  made  the 
tone  of  the  Profession  of  Dentistry. 

It  is  a  blessed  thing  for  the  patients  that  a  few  men  have  de- 
viated from  this  practice,  and  in  despite  of  deviation  have  had 
the  strength  to  swim  ;  for  the  most  of  those  who  have  done  so, 
have  been  forced  under  incontinently. 

It  is  a  blessed  thing  for  the  salvation  of  teeth,  and  for  the 
consequent  health  and  comfort  of  this  rising  generation,  that 
the  appeals  from  those  who  have  thus  "departed"  from  these 
old  time  landmarks,  are  arousing  the  members  to  a  sense  of  the 
need  for  inquiry,  investigation,  and  experimentation. 

I  trust,  and  firmly  believe,  that  it  will  prove  a  blessed  thing 
for  dentists  and  for  dentistry.  I  therefore  teach  that  the  or- 
dinary pin-head  cavities  are  those  in  which  the  work  of  saving 
teeth  is  to  be  commenced;  that  it  may  with  propriety  be  inferred 
that  a  material  which  will  do  well  in  emergent  cases  will  also 
do  well  in  the  control  of  trifling  lesions ;  that  a  material  which 
is  easy  of  manipulation  will  be  less  demoralizing  in  the  using, 
to  the  young  sufferer,  than  would  be  a  material  requiring  great 
skill  and  persevering  labor  on  the  part  of  the  operator  and 
commensurate  quiet  endurance  upon  the  part  of  the  patient; 
that-  a  material  which  will  average  more  durable  work  than 
gold,  in  difficult  cases,  may  properly  be  accredited  with  the 
capability  for  making  more  durable  work  than  gold,  as  its 
"average,"  in  easy  cases;  that  thus  it  is  but  reasonable  to  de- 
duce that  a  marked  increase  of  successful  effort  would  result 
from  the  employment  of  amalgam  an  place  of  gold  in  such  or- 
dinary cavities  as  are  so  situated  as  to  require  a  tilling  material 


GENERAL    CONSIDERATIONS.  119 

possessing  the  physical  characteristic  of  ample  resistance  to  at- 
trition during  mastication. 

It  was  in  furtherance  of  this  view  that  I  spoke  as  I  did  upon 
the  occasion  of  the  presentation  of  the  "  New  Departure  "  prin- 
ciples and  practice,  saying,  "Front  teeth,  par  excellence,  are 
filled  and  refilled  with  gold,  as  the  best  that  can  be  done,  until 
pulp  after  pulp  dies,  tooth  after  tooth  becomes  discolored  and 
crumbles  away,  root  after  root  is  extracted,  and  plate  after 
plate  is  inserted.  This  is  stereotyped  practice,  and  I  defy  con- 
tradiction of  the  statement."  "  /  think  that  a  liberal  allowance 
of  gutta-percha  and  amalgam  fillings  in  these  very  teeth,  while 
yet  the  cavities  are  only  pin-head  cavities,  would  be  a  step  in 
advance  of  this.'1 

"  This  is  still  talk;  it  makes  quiet;  but  it  is  what  I  have  come 
to-night  to  say." 

Large  Cavities. —  It  would  seem  to  require  no  argument  to 
show  that  in  proportion  as  cavities  increased  in  size,  so  would 
the  demand  increase  for  such  service  as  had  proven  effective  for 
the  retardation  of  the  loss  of  tooth-tissue  in  teeth  largely 
affected  by  caries.  It  is  nevertheless  true  that  positions 
already  begin  to  multiply  which  render  the  employment  of 
amalgam  in  these  cases  additionally  advantageous.  With 
every  grade  of  cavity  enlargement,  the  labor  of  introducing 
a  gold  filling  becomes  greater  in  quite  accurate  ratio,  while  a 
notable  difference  in  size  of  cavity  makes  but  little,  if  any,  in- 
creased labor  attendant  upon  the  introduction  of  amalgam. 
The  expense  of  gold  filling  is  also  quite  in  consonance  with 
the  size  of  the  filling  — •  relativity  of  position  being  conceded 
—  while  this  is  but  very  little  changed  in  the  use  of  amalgam, 
whether  the  cavity  be  "  ordinary  "  or  "  large."  The  conductiv- 
ity of  a  filling  is  to  be  considered  as  detrimental  in  exact  pro- 
portion to  pulp  approach,  and,  in  this  regard,  amalgam,  with 
its  comparatively  low  conducting  power,  gains  in  superiority 
over  gold  with  the  loss  of  every  successive  stratum  of  dentine. 
Thus,  on  the  varied  score  of  tooth-conservation,  saving  of  labor 
and  of  time,  saving  of  expense  and  saving  of  pulps,  amalgam 
presents  its  claims  of  superiority  to  gold  for  the  filling  of  large 
cavities  of  decay. 

Enormous  Cavities. — To  such  patients  as  have  had  experience 


120  PLASTICS    AND    PLASTIC    FILLING. 

in  the  filling  of  enormous  cavities,  as  demonstrated  by  the  two 
schools  of  gold  and  plastic  dentistry,  any  discussion  of  the 
methods  and  results  seems  purely  ridiculous.  I  cannot  place 
it  better  than  it  was  done  by  one  of  my  patients  who  had 
enjoyed  more  than  a  decade  of  years  of  each  kind  of  practice 
after  he  had  arrived  at  an  appreciative  time  of  life.  He  said, 
"  If  one  lived  five  or  six  thousand  years,  and  it  had  been  posi- 
tively demonstrated  that  it  was  a  great  deal  better  to  fill  teeth 
with  gold,  I  might  think  of  returning  to  that  kind  of  practice, 
but  for  this  paltry  seventy  years,  give  me  plastics!  " 

This  is  the  view  from  the  patients'  side  of  the  question ;  and 
is  it  to  be  supposed  that  their  comfort,  their  time,  their  health, 
their  strength,  and  their  teeth  are  of  more  importance  to  their 
dentists  than  to  themselves  ?  And  yet,  this  is  the  dental  view, 
and  so  the  teachings  continue  that  it  is  better  to  fill  ''  enormous 
cavities"  with  gold. 

It  is  conceded  that  it  is  exceedingly  difficult  to  do,  but,  if 
well  done,  it  is  a  proof  of  superior  skill;  it  is  conceded  that 
the  expenditure  of  time  is  vastly  greater  with  gold  than  with 
amalgam,  but  it  is  taught  that  the  difference  in  result  is  pro- 
portionately better ;  it  is  conceded  that  the  expense  is  threefold, 
fourfold,  tenfold,  that  of  amalgam,  but  that  with  this  it  is  com- 
pensating,  and  eminently  so ;  it  is  conceded  that  in  this  work 
the  drain  upon  the  vital  force,  of  both  patient  and  operator,  is 
something  fearful  to  contemplate,  but  it  is  said  that  the  beauty 
and  utility  of  that  which  is  produced  is  worth  it  all. 

Now,  I  ask  close  examination  of  all  this ;  I  ask  long  and 
careful  experimentation  in  regard  to  this ;  I  ask  that  it  shall 
be  done  with  knowledge  as  its  basis,  throwing  aside  that  easy 
soother  of  conscience,  that  salve  of  professional  pride,  that 
facile  cover  for  ignorance  which  has  been  so  frequently,  and 
with  such  complacent  suavity,  referred  to  as  "judgment."  I 
ask  that  there  shall  be  no  more  of  this  perversion  of  language. 
I  would  have  it  admitted  that  without  knowledge  there  can  be 
no  "judgment;"  and  I  would  have  it  felt,  and  earnestly  felt, 
that  in  this  matter  all  should  recognize  the  power  for  good 
which  would  ensue  from  the  combination  of  knowledge  and 
judgment. 

I  have  worked  long  and  hard  to  demonstrate  the  fact  that 


GENERAL    CONSIDERATIONS.  121 

the  weight  of  evidence  is  in  favor  of  the  filling  of  enormous 
cavities  with  amalgam  instead  of  gold.  I  have  taken  dentures 
by  the  hundred  which  had  been  abandoned,  by  both  patients 
and  operators,  upon  the  score  of  utter  worthlessness,  upon  which 
months  of  time,  hundreds  of  dollars,  and  mountains  of  agony 
had  been  expended,  with  no  other  return  than  repeated,  signal 
failure,  and  with  plastics,  and  mainly  amalgam,  have  kept  them, 
SATISFACTORILY,  in  working  order,  year  after  year. 

That  which  has  been  done  can  surely  be  more  easily  done 
again.  With  all  the  guiding  experience  of  the  past,  with  all 
the  improvements  in  composition,  preparation,  adaptation,  and 
manipulation,  it  will  be  found  that  but  little  inquiry  will  be 
needed  to  prove,  first,  that,  as  a  mass,  enormous  gold  fillings  are 
not  compensating,  especially  to  patients,  and  second,  that  a  pi'op- 
erly  composed,  properly  prepared,  and  properly  introduced 
amalgam,  will  prove,  in  truth,  an  advantageous  "royal  metallic 
succedaneum." 

Entire  Crowns. —  It  is  quite  frequently  the  case  that  caries 
continues  progressing  in  despite  of  all  efforts,  local  and  consti- 
tutional, operative  and  medicinal,  until  the  crowns  of  teeth  are 
either  completely  destroyed  or  are  rendered  so  frail  as  to  be 
broken  off  during  mastication.  It  is  also  very  frequently 
noted  that,  although  decay  still  progresses  until  the  dentinal 
portion  of  the  roots  is  almost  gone,  the  cemental  portion  main- 
tains its  integrity  in  a  remarkable  manner,  and  thus,  remains 
of  roots  are  in  position  for  fifteen  or  twenty  years  after  their 
cro  \vns  have  been  lost. 

It  is  these  facts  which  have  led  to  the  practice  of  "utilizing 
roots,"  as  it  is  called,  for  the  purpose  of  "  pivoting,"  "  grafting," 
or  "building  on"  crowns. 

Various  methods  and  very  ingenious  devices  have  been  sug- 
gested for  the  securing  of  natural  crowns  and  crowns  of  porce- 
lain, amalgam,  and  gold  ;  and  for  this  securing,  amalgam  has 
already  been  extensively  and  very  advantageously  employed, 
and  bids  fair  to  almost  entirely  supplant  every  other  material. 
It  is  probable  that  large  and  elaborate  "  crownings  "  will  be 
done  with  gold,  for,  perhaps,  many  years  yet,  but  it  is  not 
likely  that  such  work  will  continue  to  be  permitted,  much 
less  be  demanded,  by  patients,  as  the  evident  practicality  of 


122  PLASTICS    AND     PLASTIC     FILLING. 

plastics  lias  even  now  resulted  in  their  being  very  largely  pre- 
ferred. 

The  first  use  for  amalgam  in  cases  requiring  entire  crowns, 
is  the  "  building  up  "  of  the  crown  with  this  material.  This  is 
done  by  one  of  three  methods  and  by  the  use  of  either  one, 
two,  or  three  kinds  of  alloy. 

If  the  decay  of  the  crown  has  progressed  so  slowly  as  to  per- 
mit the  gradual  covering  of  the  pulp  by  deposition  of  second- 
ary dentine,  thus  leaving  a  crownless  root  containing  a  well- 
covered  vital  pulp,  the  face  of  the  root  is  prepared  with  espe- 
cial regard  given  to  the  strength  and  solidity  of  the  periphery 
and  to  the  leaving  of  all  living  —  though  softened — dentine 
over  the  pulp.  Eetaining  slots  are  then  made  by  drilling,  with 
spear-pointed  drill,  lines  of  two  or  more  drill-pits  at  different 
selected  places,  and  then  connecting  the  pits  by  using  a  fissure- 
drill  or  small  oval  burr.  These  should  be  filled  with  an  amal- 
gam made  from  "contour"  alloy  —  approximate,  silver  58,  tin 
37,  gold  5-^- for  its  qualities  of  non-shrinkage,  quick-setting, 
and  eminent  edge-strength.  The  fillings  should  be  made  a 
little  more  than  full,  and  rounded  out,  that  surface  for  adhesion 
may  be  afforded  to  the  tooth-conserving  amalgam  —  made  from 
submarine  alloy  —  with  which  a  base  for  the  crown  should  be 
built  out  to  the  edge,  covering  the  entire  face  of  the  root.  The 
crown  should  then  be  built  on  with  contour  amalgam,  which, 
by  alternate  layers  of  plastic  mix  and  wafers,  can  be  carried  up, 
shaped,  hardened,  and  finally  finished  at  one  sitting,  and  which 
will  set  sufficiently  well  in  an  hour  to  preclude  any  liability  to 
accident  if  guarded  with  even  reasonable  care. 

If  the  crown  is  upon  a  bicuspid  root,  or  upon  that  of  a  first 
molar,  which  shows  either  during  speaking  or  laughing,  the 
buccal  portion  of  the  crown  should  be  cut  out  as  for  "  facing  " 
—  see  Technicals  —  and  the  concavity  be  filled  with  facing 
amalgam.  It  will  be  seen  that  by  this  method  the  varied  re- 
quirements of  strong  anchorage,  excellent  root  conservation, 
rapid  and  strong  crown  formation,  and  beauty  in  presentation 
are  all  satisfactorily  met.  I  have  made  some  very  serviceable 
and  nice-looking  operations  of  this  kind  upon  cuspid  roots. 

If  decay  has  progressed  quickly,  and  a  pulp  exposure,  devital- 
ization  and  extirpation  has  ensued,  the  operation  of  crown- 


GENERAL    CONSIDERATIONS.  123 

building  is  much  simplified  as  abundant  retention  is  most 
readily  obtained.  In  these  cases  the  great  advantage  of  amal- 
gam becomes  apparent  in  matters  of  vital  importance  connected 
with  the  duration  of  possible  tooth  maintenance,  for  the  two 
great  questions  of  irritation  from  dental  manipulation,  and  easy 
possibility  of  arranging  for  relief  from  probable  future  trouble 
are  most  perfectly  solved  in  the  using  of  this  filling  material. 
The  canals  having  been  filled  with  glycerine,  into  which  is 
passed  taper-twisted  canal  dressings  of  cotton  wool  dipped  in 
oil  of  cloves,  these  are  covered  with  gutta-percha  in  such 
manner  as  that  the  floor  of  the  pulp  cavity  is  lined  with  this 
and  the  filling  is  shaped  into  a  hemisphere.  Around  this,  in 
undercut  grooves,  is  anchored  the  amalgam  filling,  which  is 
then  built  up  into  shape  and  allowed  to  harden  for  fifteen  or 
twenty  minutes,  or  until  it  is  enough  set  to  permit  of  easy 
cutting  without  danger  of  breaking.  An  entrance  is  now 
made,  by  careful,  gentle  drilling  or  cutting  through  the  filling 
into  the  gutta-percha.  This  entrance,  if  upon  an  articulating 
surface,  is  then  almost  entirely  filled  with  gutta-percha,  over 
which  is  placed  a  covering  of  amalgam.  If  it  is  upon  any 
surface  not  exposed  to  attrition,  it  is,  of  course,  completely 
filled  with  gutta-percha.  If  the  relief  route  is  closed  with 
amalgam,  it  should  always  be  done  with  "  facing "  amalgam, 
as  this  will  leave  a  distinct  demarcation  indicative  of  position 
of  "tap." 

The  third  method  of  attaching  amalgam  crowns  is  by  pins 
or  wire-loop ;  for  this,  either  platinum  or  soft  iron  wire  may 
be  used.  I  have  attached  a  large  number  of  crowns  by  each 
of  these  two  kinds  of  wire,  and  I  can  see  no  advantage  which 
platinum  possesses  over  iron  except  that  it  is  more  easily  bent. 
I  have  therefore  gradually  settled  into  the  habit  of  using  iron 
wire  in  cases  where  the  pins  were  to  be  left  straight  and  were 
required  to  be  strong;  and  platinum  where  they  were  looped 
or  bent,  and  were  likely  to  require  more  accurate  bending  after 
being  secured  in  position. 

For  either  pins  or  wire-loop,  one  end  should  be  rivet-headed, 
and  in  some  cases  of  straight  pins  it  is  requisite  that  they 
should  be  double-headers ;  for  the  making  of  these  I  use  a 
slide  screw-plate,  into  the  screw-hole  of  which  the  pin  is 


124  PLASTICS    AND    PLASTIC    FILLING. 

placed,  and,  when  clamped  by  the  slide,  very  quickly  double- 
headed  with  a  riveting-hammer. 

Drill-holes,  of  the  size  of  the  rivet-head,  having  been  made, 
and  spheroided  with  a  round  or  oval  burr,  the  pin  or  loop  is 
placed  in  position,  and  secured  with  amalgam.  This  is  al- 
lowed to  set,  and  these  then  form  a  firm  reliance  for  the  reten- 
tion of  the  crown. 

I  wish  here  to  speak  of  the  advantage  of  this  method  of 
securing  pins  over  that  of  screwing  them  into  the  dentine.  For 
more  than  fifty  years,  the  principle  of  screw  attachment  has 
been  offered  for  the  purpose  of  fastening  crowns  upon  roots, 
but,  so  far  as  I  have  seen,  the  results  show  that  it  is  not  a 
desirable  method.  The  efforts  during  mastication  tend  to 
produce  an  imperceptible  loosening,  which,  trifling  as  it  is, 
increases  quite  rapidly  after  being  once  established.  Soon 
the  motion  becomes  observable,  and  then,  almost  immediately, 
the  screw-thread,  acting  as  a  file,  cuts  the  pin  loose,  and  the 
crown  drops  off. 

Just  the  opposite  result  will  ensue  from  the  rivet-head  and 
filling  securing,  for  these  have  been  proven  to  hold  until  the 
wiie  has  been  broken,  or  wrenched  out  by  fracture  of  the  root, 
or  undermined  by  the  progress  of  recurring  decay. 

The  second  use  for  amalgam,  in  cases  requiring  entire  crowns, 
is  for  the  purpose  of  attaching  gold  crowns.  These  are  made 
by  bending  a  ribbon  of  pure  gold,  cut  from  plate  made  of  gold- 
foil  scraps  or  old  gold  fillings,  and  soldering  it  to  a  ring  with 
an  approximate  fit  for  the  face  of  the  root  to  be  crowned.  The 
anchorage  is  then  obtained,  and  a  filling  of  submarine  alloy  is 
made  which  extends  a  short  distance  out  from  the  gum.  When 
this  is  a  little  hardened,  the  gold  crown  is  pressed  into  position, 
cutting  through  the  amalgam,  and  thus  forming  a  joint  at  the 
neck  of  the  root,  not  by  slipping  over  it  and  banding  it,  but 
by  resting  upon  it,  which  joint  is  then  made  perfect  by  tapping 
the  still  workable  amalgam  accurately  into  apposition  with  the 
upper  edge  of  the  encircling  ring  of  gold.  Contour  amalgam 
is  now  employed  for  filling  the  entire  crown,  and  thus  it  is 
secured  upon  the  root.  One  might  naturally  suppose  that  the 
mercury  from  the  amalgam  would  permeate  and  discolor  the 
gold,  but  it  does  not  do  this,  and,  from  this  fact,  enables  us 


GENERAL    CONSIDERATIONS.  125 

to  utilize  this  facile  and  durable  method  of  fastening  such 
crowns.  This  style  of  work  formed  m}*  "  intermediate "  be- 
tween the  gold  crowns  which  I  formerly  made  with  foil  and 
the  amalgam  or  amalgam  and  porcelain  crowns  which  I  now 
use  almost  exclusively. 

The  third  use  for  amalgam,  in  cases  requiring  entire  crowns, 
is  for  the  replacing  of  natural  crowns  which  have  been  broken 
off.  This  is  sometimes  a  very  gratifying  operation,  both  to 
patient  and  practitioner,  for  it  is  usually  alike  pleasing  and 
unexpected  to  the  patient  to  have  such  restoration  made,  and 
it  produces  a  result  which,  for  perfection  of  appearance,  cannot 
be  equalled  by  any  other  process. 

The  crown,  possessing  as  it  does  all  the  special  peculiarities 
which  pertain  to  that  individual  location,  if  replaced,  gives  to 
the  work  a  harmony  with  surroundings  which  cannot  be  other- 
wise attained ;  and  it  is  for  this  reason  that  it  is  not  only  war- 
rantable, but  eminently  desirable  that  the  attempt  should  be 
made,  especially  for  lady  patients,  and  especially  again  for  the 
conservation  of  facial  identity  or  great  personal  beauty. 

For  this  purpose  the  crown  should  be  so  drilled  as  to  obtain 
the  necessary  mechanical  hold  for  its  part  of  the  securing 
iilling.  The  root  should  be  drilled  out  deeply,  and  bell- 
shaped  at  the  entrance,  so  as  to  give  broad,  strong  retaining 
surface  for  the  amalgam  at  the  union  between  crown  and  root. 
The  labial  portion  of  the  crown  —  it  is  supposed  that  this  op- 
eration would  not  be  deemed  advisable  for  any  tooth  posterior 
to  a  cuspid  —  should  be  lined  either  with  a  very  thin  lining  of 
<>xy -chloride  of  zinc  —  in  which  there  is  little  or  no  strength  — 
or  a  somewhat  thicker  lining  of  facing  amalgam,  which  may 
subserve  the  purpose  of  increasing  the  strength  of  attachment ; 
the  object  of  which  is  the  prevention  of  discoloration,  for 
neither  are  strong  enough  to  rely  upon  for  support. 

The  root  should  now  be  nearly  filled,  and  the  tooth  having 
been  placed  accurately  in  position,  and  being  held  either  by 
the  finger  and  thumb,  or  retained  positively  by  gutta-percha, 
plaster  of  Paris,  oxy-chloride  of  zinc,  or  zinc-phosphate  sup- 
ports, mesially,  labially,  and  distally,  should  now  be  secured  by 
contour  amalgam.  This  should  be  allowed  to  set  for  at  least 
an  hour,  when  the  supports  may  be  carefully  removed.  Such 


126  PLASTICS    AND    PLASTIC    FILLING. 

teeth  should  not  be  bitten  upon  for  a  day  or  two,  if  it  is  possible 
to  avoid  it,  for  it  is  very  essential  to  success  that  the  amalgam 
should  be  thoroughly  set  before  it  is  subjected  to  the  slightest 
strain.  For  increased  strength,  a  small  platinum-pin  may  be 
secured  in  the  root  and  permitted  to  pass  into  or  through  the 
crown,  as  in  a  Bonwill  pivot. 

The  fourth  use  for  amalgam  in  these  cases  is  for  the  securing 
of  natural  or  porcelain  crowns  which  have  been  fitted  to  crown- 
less  roots.  From  what  has  been  said  relative  to  the  replacing 
of  crowns  which  have  been  broken  off,  it  will  require  but  few 
words  to  present  this  modification  of  that  operation  ;  but  it 
will  be  seen,  upon  slight  presentation,  that  modifying  considera- 
tions do  exist.  A  crown  which  had  been  broken  off  would, 
under  almost  all  ordinary  circumstances,  have  been  subject  to 
extensive  decay  prior  to  tractive;  while  a  selected  crown  — 
either  natural  or  porcelain — would  be  perfect  in  contour.  The 
one,  the  porcelain,  would  be  so  drilled  and  prepared  internally, 
and  at  its  neck,  as  to  require  but  trifling  adaptation  by  grind- 
ing, and  subsequent  securing  by  contour  amalgam ;  the  other, 
the  natural,  would  require  drilling  and  internal  shaping  of 
cavity  to  correspond  with  the  prepared  cavity  of  an  artificial 
tooth ;  and  it  should  then  be  "  lined  "  to  prevent  discoloration. 

Pivoting  Teeth.  —  In  this  work,  as  in  the  whole  line  of  opera- 
tive dentistry,  amalgam  has  wrought  most  radical  changes ;  it 
seems  to  have  supplanted  the  entire  range  of  round  and  square 
box- work  with  split-pin — gold  —  pivots;  it  has  largely  taken 
the  place  of  foil  for  securing  these  tubes  and  boxes,  even  if  they 
are  used.  It  has  only  gutta-percha  as  a  rival  for  the  securing 
of  metallic-pin  pivots ;  and  it  welcomes  the  aid  of  gutta-percha, 
for  it  recognizes  in  it  a  most  notable  plastic.  It  has  essentially 
modified  every  phase  of  pivoting,  and  has  rendered  that  opera- 
tion, which  was  formerly  either  disgusting  —  wooden  pin  in 
plain  root  —  or  very  tedious,  painful,  and  expensive  —  back- 
stayed-plate  tooth  built  in  with  gold  foil  —  a  painless,  compara- 
tively inexpensive,  and  cleanly  piece  of  work ;  equally  beauti- 
ful in  appearance ;  equally  durable,  and  requiring  but  an  hour 
or  two  for  its  doing. 

Its  first  great  change  was  the,  supplanting  of  the  increase  of 
size  of  wooden  pivots,  as  the  roots  became  more  and  more  de- 


GENERAL    CONSIDERATIONS.  127 

cayed,  by  the  filling  of  the  enlarged  pivot-hole  with  amalgam, 
and  the  drilling  of  such  sized  hole  as  permitted  a  return  to  the 
original  size  of  wooden  pin.  This  was  a  great  step  in  advance, 
as  by  it  many  a  root  was  saved  for  many  a  year  of  usefulness, 
and  even  retained  until  further  modifications  resulted  in  the  re- 
pivoting  of  teeth,  in  a  superior  manner,  upon  roots  which  had 
already  supported  pivot  teeth  for  more  than  a  dozen  years,  and 
for  which  fears  as  to  their  possible  long  continuance  had  been 
entertained  many  years  before,  as  pin  after  pin  had  been  in- 
troduced with  biennial  regularity. 

The  day  of  wooden  pins  is  slowly  passing  away,  and  yet  this 
use  of  amalgam  will  probably  continue  for  a  long  time  to  come, 
and  will  be  resorted  to,  as  it  now  is,  for  foundations  for  first 
wooden-pin  pi  votings  instead  of  permitting  the  roots  to  become 
almost  ruined  before  lining  them. 

But  the  marked  influence  of  amalgam  over  pivoting  is  most 
strikingly  exemplified  in  the  operations  as  variously  proposed 
by  Dr.  Bon  will,  Dr.  Gates,  and  myself. 

Bonwill  Pivot.  —  Select  pivot-tooth,  —  Bonwill's ;  prepare 
root,  and  fit  crown;  fill  root  with  "usual"  amalgam  —  soft 
make  —  and  force  entrance  for  platinum-pin  in  amalgam  with 
a  pointed  instrument.  Grasp  pin  —  which  should  be  of  right 
length,  tri-flattened,  and  barbed  —  with  forceps,  and  press  it 
forcibly  home.  Tamp  amalgam,  to  be  sure  that  it  well  secures 
pin.  This  pin  may  equally  well  be  rivet-headed  and  filled  into 
the  root.  Replace  crown  to  see  that  it  fits.  It  is  advantageous 
to  bend  pin  so  that  it  rests  against  palatal  side  of  hole  in  crown, 
as  thus  the  crown  is  retained  nicely  in  place.  Fill  base  of 
crown  through  to  palatal  side  with  amalgam  —  plastic  —  and 
with  one  finger  over  palatal  hole  press  firmly  into  position  by 
twisting,  and  afterwards  tapping,  by  wooden  pin,  with  mallet. 
The  fingers  will  be  best  if  the  amalgam  is  not  too  stiff;  then 
"  wafer  "  to  harden  the  amalgam.  After  it  is  thoroughly  hard, 
smooth  off  the  exposed  portion  of  filling  and  the  end  of  the 
platinum-pin  if  protruding. 

Any  pivot-crown  may  be  used  for  this  method  by  drilling  a 
hole  through  it  with  a  "  diamond-drill ;"  then  reaming  out  the 
base  well  towards  the  periphery  and  countersinking  on  the 
palatal  face. 


128  PLASTICS    AND    PLASTIC    FILLING. 

I  have  set  quite  a  number  of  these  "  pivots,"  and  have  reason 
to  be  well  satisfied  with  the  firmness,  cleanliness,  and  appear- 
ance of  the  results,  and  with  the  reasonable  facility  with  which 
the  operation  is  performed. 

The  Gates  Pivot. —  The  Gates  and  the  Bonwill  crowns  are 
hereafter  (Dec.  1880),  to  be  considered  identical  and  known  as 
the  Gates-Bonwill  crowns.  Dr.  Gates  held  the  original  patent 
of  a  perforated  crown  with  an  enlarged  basal  orifice.  Dr.  Bon- 
will  employed  the  same  general  form,  but  with  a  simpler  method 
of  setting.  Both  recognize  that  to  amalgam  is  due  the  signal 
success  in  the  reliability  of  these  operations ;  but  Dr.  Gates 
employs  a  crown -holder  in  most  cases.  He  places  a  post,  tem- 
porarily attaching  the  crown  with  wax  in  the  exact  position 
desired;  then  with  small,  trough-shaped  tray  encases  it  by  im- 
pression. The  impression  when  trimmed  will  show  a  vertical 
section  of  the  adjoining  tooth  at  each  end,  and,  when  set  hard, 
will  support  the  crown  while  being  imbedded  on  the  amalgam. 
To  hasten  the  operation,  use  modelling  composition  instead  of 
plaster.  The  post  is  of  steel,  and  has  a  special  screw-thread 
whereby  it  reaches  its  position  by  three  or  four  turns  only.  It 
is  also  provided  with  two  grooves  lengthwise  which  prevent 
air-compression  in  the  root  and  afford  a  firm  grasp  for  insertion, 
which  is  readily  accomplished  at  any  angle  in  the  mouth  by  a 
convenient  carrier.  He  also  employs  a  safety-burr  for  rapid  and 
definite  formation  of  retaining-points  in  the  stronger  walls  of 
the  root.  It  consists  of  a  compound  burr,  practically  t\v<>  wheels 
formed  slightly  apart  on  the  same  mandrel,  the  uncut  space  be- 
tween them  preventing  too  near  approach  to  the  cementuin. 
Short  grooves  in  the  face  of  the  countersink  are  also  some- 
times useful  as  preventive  to  the  danger  of  subsequent  split- 
ting of  the  roots.  In  setting,  he  packs  the  enlarged  pulp- 
canal  nearly  full  of  amalgam,  then  with  twist-drill  forms  the 
hole  in  which  the  post  taps  its  own  screw-thread.  Before  tamp- 
ing the  amalgam  around  the  post,  place  the  crown,  as  the 
position  of  the  post  can  now  be  readily  corrected  if  wrong. 
Build  up  around  the  post,  and,  if  more  convenient,  carry  part 
of  the  amalgam  to  its  place  in  the  crown  itself.  By  removing 
and  replacing,  using  oscillating  pressure  and  mallet-strokes  on 
the  crown-holder,  the  position,  by  the  guides  and  the  impression 


GENERAL    CONSIDERATIONS.  129 

on  the  amalgam,  is  proven  correct.  The  crown  is  then  freed 
from  the  holder,  and,  after  giving  a  short  time  for  the  amalgam 
to  harden,  is  replaced  and  secured  permanently  to  the  free  end 
of  the  post  by  filling  with  amalgam  through  the  coronal 
opening. 

Flagg  Pivot. —  Select  plate-tooth,  fit  it  to  root,  and  bevel  it 
from  near  the  pin  —  cervical  —  or  pins,  if  cross-pins,  to  the 
labio-cervical  edge.  Solder  a  platinum-pin  to  it  as  a  backstay 
and  pivot  combined,  leaving  it  rough  or  grooved  on  both  sides 
of  pin  for  a  retaining  hold  to  the  finishing  palatal  amalgam. 

Fill  the  root,  which  is  treated,  prepared  for  strong  mainte- 
nance of  filling,  and  "bell-muzzled,"  or  "open-mouthed,"  with 
a  good  iisual  or  contour  alloy  —  quick-setter;  non-shrinker ; 
good  edge-strength.  I  prefer  to  give  this  a  day  to  harden 
thoroughly,  but  in  case  of  need  it  may,  with  care,  be  worked 
in  an  hour  or  two. 

Into  the  root-filling,  drill  a  hole  rather  larger  than  the  plat- 
inum-pin, as  near  to  the  palatal  portion  of  the  filling  as  possi- 
ble, and  directed,  slantwise,  to  the  apical  centre  of  root-filling ; 
then  "  fissure-drill "  the  hole  towards  the  labial  portion  of  the 
filling,  trying  the  tooth  until  it  sets  just  right,  with  the  pivot- 
pin  pressing  hard  against  the  labial  side  of  the  now  oval  pivot- 
hole.  By  this  method  the  tooth  is  accurately  placed  in  position, 
and  easily  held  firmly  in  place,  while  the  pin  is  secured  by  filling 
the  pivot-hole  with  amalgam. 

Let  this  harden  for  half  an  hour,  and  then  add  amalgam,  in 
contour,  to  the  root -filling  and  palatal  face  of  the  porcelain 
tooth.  It  is  at  this  point  of  the  operation  that  the  need  for 
"  bevelling  "  the  cervical  portion  of  the  tooth  is  demonstrated  ; 
for,  by  this  bevel,  one  is  enabled  to  make,  by  filling,  a  perfectly 
tight  joint  at  the  labio-cervical  junction  of  tooth  with  root, 
and  also  to  secure  a  strength  of  amalgam  'equal  to  the  entire 
surface  of  root-filling. 

This  makes  a  strong,  cleanly,  and  satisfactory  operation. 

"Guarding"  or  repairing  gold  fillings,  and  refilling  cavities 
from  which  gold  fillings  have  been  lost,  in  teeth  which  still  con- 
tain gold  fillings. 

We  have  now  reached  a  singularly  vexed  question  in  den- 
tistry, viz.,  the  use  of  two  rnetals  in  one  tooth,  or,  possibly 
9 


130  PLASTICS    AND    PLASTIC    FILLINO. 

more  dubious,  the  use  of  two  metals  in  one  cavity.  In  the 
discussion  of  this  question,  I  shall  regard  amalgams  as  metallic 
compounds,  each  of  which  is  possessed  of  that  definite  poten- 
tial, conductivity,  resistance  to  tarnish,  etc.,  which  makes  of  it, 
practically,  a  metal,  and  thus  renders  fillings  of  tin  and  gold, 
and  amalgam  and  gold,  equally  bi -metallic,  dentally.  There  is 
scarcely  any  point  which  has  been  more  frequently  spoken  to 
in  discussion  than  this,  and  probably  no  one  upon  which  more 
theory  and  less  practice  has  been  expended  in  antagonism. 

From  the  fact,  which  has  been  alluded  to,  that  galvanic  ac- 
tion can  be  excited  by  fillings  of  different  metals  in  close  prox- 
imity, and  is  variously  demonstrated  by  metallic  taste,  pain, 
shock,  and  even  spark,  it  has  been  largely  concluded  that  the 
placing  of  such  must  necessarily  be  detrimental. 

Reference  to  discussions  upon  this  point  will  show  that 
while  only  vague  ideas  of  how  this  combination  could  work 
injury  were  enunciated,  positive  belief  that  it  would  do  so  was 
unhesitatingly  and  forcibly  expressed ;  and  this,  too,  strangely 
enough,  without  any  distinction  as  to  relative  placing  of  metal ; 
whether  equally  or  unequally  exposed,  or  even  \vhether  both 
were  exposed  or  one  completely  covered. 

To  such  extent  is  this  peculiar  discussion  carried  that  the 
same  gentlemen  are  found  inveighing  most  decidedly  against 
the  partial  filling  of  ordinary  cavities  of  decay  with  tin,  and 
the  covering  of  this  metal  with  gold,  upon  the  ground  that 
the  union  of  two  metals  in  one  cavity  would  produce  pulpitis, 
death  of  the  pulp,  and  eventually  alveolar  abscess,  and,  at 
other  times,  are  equally  strong  in  their  advocacy  of  the  em- 
ployment of  sheet-lead  as  a  pulp-protector  (!)  in  cavities  con- 
taining almost  exposed  pulps,  and  the  filling  over  it  with  gold. 
This  appears  to  have  been  done  with  the  idea  that  lead  was  not 
a  metal ! 

Views  upon  this  "  two-metal  question  "  have  become  modi- 
fied by  time  and  observation,  until  it  was  very  recently  an- 
nounced — "  Cosmos,"  Nov.,  1879,  p.  626  — that  observation  had 
shown  "  that  amalgam  and  gold  may  be  used  in  the  same  tooth, 
and  in  immediate  contact,  with  no  unfavorable  results,  notwith- 
standing the  theories  which  have  obtained  to  the  contrary" — 
the  italics  are  mine ;  while  to  a  question  regarding  the  conse- 


GENERAL    CONSIDERATIONS. 

quences  of  filling  two  proximate  cavities  respectively  with 
gold  and  amalgam,  contact  being  permitted,  the  same  speaker 
replied  that  he  would  "not  have  allowed  them  to  touch.'1'' 

The  deduction  is  that  it  might  be  that  no  unfavorable  conse- 
quences would  ensue,  even  though  the  metals  were  in  contact ; 
but  that  contact  should  be  avoided,  if  possible. 

During  the  same  discussion,  reference  is  made  to  my  claim 
that  "  the  relation  of  the  two  is  the  salvation  of  the  tooth," 
which  I  do  claim  most  decidedly. 

I  would  suggest  especial  reading  of  the  remarks  of  Dr.  Bon- 
will, —  same  discussion,  page  631, —  for  it  is  very  well  known 
that  this  gentleman  is  one  of  the  most  thoroughly  informed 
electricians  of  the  dental  profession. 

His  view  is,  that  when  gold  touches  amalgam  in  proximate 
teeth,  the  teeth  should  be  so  pressed  apart  and  the  fillings  so 
contoured  as  that  "  when  they  come  together  again  no  ordinary 
attrition  will  cause  them  to  separate"  With  this  I  agree. 

It  is  now  eighteen  years  since  my  attention  was  directed  to 
the  systematic  investigation  of  this  subject.  I  was  led  to  this 
by  the  placing  under  my  charge  of  a  tooth  —  right  lower  wis- 
dom —  which  had  a  large  cavity  upon  the  articulating  face,, 
that  had  been  filled  for  nearly  twenty  years  with  gold,  and  an- 
other upon  the  buccal  face,  which  had  been  filled  three  times 
during  the  same  period  with  the  same  material.  The  patient 
was  then  fifty-nine  years  of  age.  I  suggested  the  trial  of  amal- 
gam in  the  cavity  from  which  the  gold  had  so  frequently  failed, 
and  the  suggestion  was  accepted. 

A  few  days  after  the  operation,  the  patient  returned  with  the 
statement  that  a  metallic  taste  was  frequently  perceptible,  and 
that  occasionally  during  mastication  a  painful  shock  had  been 
felt  in  the  filled  tooth. 

Upon  examination  and  experimentation,  I  found  that  during 
laughing  the  cheek  so  pressed  upon  the  two  fillings  as  to  make 
and  retain  gentle  connection  between  them,  giving  rise  to  metal- 
lic taste ;  and  that  during  the  mastication  of  a  piece  of  cracker 
an  occasional  sudden  and  forcible  connection  would  be  made 
which  caused  a  shock. 

It  occurred  to  me  to  connect  the  fillings  as  the  first  means  of 
preventing  shock ;  and  I  informed  the  patient  that  if  metallic 


PLASTICS    AND    PLASTIC    FILLING. 

taste  supervened,  it  would  pass  away  with,  the  discoloration  of 
the  amalgam  filling.  This  connection  was  made  by  cutting 
through  the  small  intervening  portion  of  enamel,  —  both  the 
cavities  were  large,  —  and  the  sequence  proved  the  correctness 
of  the  prognosis ;  there  were  no  more  shocks,  and  the  metallic 
taste  became  less  each  day  until  it  ceased  altogether. 

But  another  result  in  due  time  attracted  my  notice.  The 
gold  filling  upon  the  articulating  face  was  slightly  defective, 
sufficiently  so  for  me  to  request  an  occasional  opportunity  for 
its  examination.  Year  after  year  passed,  and  seventeen  years 
after  —  patient  aged  seventy-six  —  I  removed  this  tooth  with 
my  fingers,  it  having  loosened  from  combined  excessive  use 
and  gum  and  process  recession,  with  the  amalgam  filling  cred- 
ited with  its  seventeen  years  of  service,  and  with  the  gold  fill- 
ing no  more  defective  than  it  was  seventeen  years  lief  ore. 

It  was  as  the  sequence  of  watching  this  filling  and  others 
resultant  from  this  experiment  for  five  years,  that  twelve  years 
previous  to  this  extraction  I  had  ventured  upon  the  statement 
to  the  class  of  the  Philadelphia  Dental  College  that  I  thought 
it  probable  that  "  the  relations  of  metals  in  bi-rnetallic  fillings 
gave  to  such  fillings  therapeutic  value,  and  that  this  value  was 
dependent  upon  the  contact  of  the  metals  and  the  exposure  of  both 
metals  to  the  fluids  of  tit?  mouth. 

It  was  this  belief  which  led  me  to  "  guard  "  with  crescents 
of  tin  the  cervical  walls  of  cavities  which  I  proposed  filling 
with  gold.  It  was  this  which  led  me  to  fill  the  crevices  around 
failing  gold  fillings,  especially  at  those  "vulnerable  spots" 
which  were  inaccessible,  and  under  gums,  with  amalgam.  It 
was  this  which  made  me  feel  warranted  in  saying  at  the  "Nc\v 
Departure"  meeting,  of  the  New  York  Odontological,  Nov.  1877, 
that  I  had,  "up  to  April,  1877,  1053  gold  fillings  of  my  own,  and 
many  other  operators',  doing  service  only  because  they  had  been 
guarded  in  this  way"  by  tin,  gutta-percha,  or  amalgam. 

Believing  that  the  injury  to  soft  dentine  which  would  arise 
from  contact  between  it  and  gold  by  difference  of  potential 
would  be  notably  counterbalanced  by  contact  again  between 
gold  and  amalgam,  I  can  readily  see  that,  as  has  been  stated  by 
Dr.  Dixon,  amalgam  fillings  might  be  serviceably  guarded  by 
gold;  while,  upon  the  same  principle,  gold  fillings  would  be 


GENERAL    CONSIDERATIONS.  138 

guarded  by  amalgam,  as  instanced  by  Dr.  Daniel  Neall;  but 
upon  principle  I  should  expect  in  a  very  soft  tooth,  one  that 
markedly  needed  help,  that  a  gold  filling  circumscribed  by  amal- 
gam would  do  longer  service  than  an  amalgam  filling  circum1 
scribed  by  gold. 

But  it  is  not  alone  for  the  simple  maintenance  of  integrity  in 
any  one  or  more  fillings,  that  I  would  advocate  the  making  of 
bi-metallic  fillings  or  the  modifying  of  fillings  already  made  of 
one  material  so  as  to  make  of  them  "bi-metallic;"  for  my  expe- 
rience in  great  numbers  of  mouths  points  to  the  conclusion  that 
such  fillings  may  be  definitely  relied  upon  for  the  making  of 
such  change  in  the  oral  fluids  as  will  be  protective  of  other 
fillings;  preventive  in  some  degree  of  caries,  curative  of  sensi- 
tiveness of  dentine,  and  even  beneficial  to  general  health. 

It  is  with  much  deliberation  that  I  have  come  to  these  con- 
clusions ;  and  yet  it  is  not  without  some  hesitancy  that  I  have 
spoken  of  them  from  the  lecture-stand,  and  now  present  them 
for  professional  consideration.  The  instances  in  which  the 
making  of  six  or  eight  such  fillings  in  mouths  where  failure 
of  fillings  was  a  constantly  recurring  thing,  and  where  exquis- 
ite sensitiveness  of  dentine  was  the  unfortunate  concomitant, 
and  where  such  failures  became  from  that  time  notably  less, 
and  markedly  in  connection  with  the  gold  fillings,  and  where 
the  sensitiveness  of  dentine  was  modified  even  to  almost  com- 
plete normality,  are  so  numerous  in  my  practice  that  I  could 
not  overlook  them  even  if  I  would.  Indeed,  these  results  have 
been  so  notable,  that  in  many  mouths  containing  partial  den- 
tures upon  gold  plates,  I  have  supplemented  my  efforts  at  pre- 
serving the  remaining  teeth  with  plastic  fillings  by  breaking  a 
tooth  or  block  from  the  artificial  work,  and  building  in  its  place 
a  tooth  or  block  of  amalgam. 

The  change,  both  local  and  systemic,  which  so  soon  occurs, 
is  too  frequent  and  too  decided  for  me  to  doubt  that  the  post 
hoc  is  a  propter  hoc. 

Fractures  of  tooth  from  fillings,  either  of  gold  or  amalgam. — 
With  the  classes  of  teeth  which  require  large  fillings,  it  is  no 
unusual  thing  to  find  cavity  walls  of  paper-like  thinness,  or 
portions  of  tooth  possessing  considerable  thickness,  but  at- 
tached to  the  roots  by  narrow  connections.  In  such  cases  a 


134  PLASTICS    AND     PLASTIC     FILLING. 

violent  contact  with  unyielding  material,  such  as  crackers, 
candies  of  certain  kinds,  pieces  of  bone,  or  oyster-shells,  etc., 
will  inevitably  crush  or  break  off  such  fragile  or  insecure 
structure. 

These  accidents  are  probably  most  frequent  with  bicuspids, 
especially  those  of  the  upper  jaw.  This  is  due  to  the  marked 
predisposition  of  these  teeth  to  decay  largely,  and  in  such  man- 
ner, mesially,  distally,  and  in  the  articulating  face,  as  to  afford, 
after  filling,  the  least  remaining  strength  for  resisting  the  dis- 
advantageous wedging  of  food  between  the  buccal  and  palatal 
cusps. 

It  is  to  avoid  this  contingency  that  Prof.  D.  D.  Smith  has 
suggested  the  advisability  of  excising  the  palatal  cusps,  and, 
in  very  rare  cases,  even  both  cusps,  of  such  frail  teeth,  and 
either  restoring  contour  with  filling  material,  or  so  filling  the 
teeth  as  to  make  of  them  thickened  cuspids.  This  operation 
will  be  recognized  as  founded  upon  correct  principle,  and  is 
rendered  peculiarly  feasible  by  the  use  of  plastics,  in  which, 
although  "  combination  "  fillings  are  almost  universally  indi- 
cated, amalgam  nevertheless  performs  the  most  important  part. 

It  will  be  noted  that  such  teeth  are  completely  "  slotted " 
through ;  the  remaining  walls  are  necessarily  thin,  and  it  is 
important  that  a  good  color  should  be  maintained,  at  least, 
buccally.  For  this  purpose  the  buccal  wall  is  lined  with  oxy- 
chloride  of  zinc,  and  the  buccal  cusp  is  so  undercut  as  to  afford 
the  strongest  possible  hold  for  the  strongest  kind  of  amalgam, — 
contour, — with  which  the  tooth  is  filled  after  having  secured  the 
cervical  portion  of  the  cavity  by  a  thin  layer  of  "  submarine." 
If  it  has  been  deemed  desirable  to  cut  off  the  buccal  cusp,  in 
consequence  of  exceeding  frailty  at  the  bucco-cervical  line,  it 
will  be  necessary  to  finish  by  the  use  of  facing  amalgam. 

But  it  is  in  the  repairing  of  ordinary  fractures  of  tooth  sub- 
stance from  fillings  of  gold  or  amalgam,  that  amalgam  most 
positively  demonstrates  its  extraordinary  capabilities;  for,  in 
.such  cases,  from  the  least  to  the  yreatest,  the  reparations  are 
made  with  almost  equal  facility. 

Every  indication  is  met,  no  matter  how  diversified,  no  mat- 
ter how  numerous,  no  matter  how  imperative !  If  a  mere 
•"shell''  has  been  "artistically"  filled  with  gold,  and  a  long 


GENERAL    CONSIDERATIONS.  135 

sliver  of  enamel  has  been  broken  out  from  the  disto-palatal 
wall,  a  more  difficult  or  annoying  piece  of  repair,  with  gold, 
could  not  well  be  imagined,  and  yet,  with  soft-mixed  •'  usual  M 
amalgam,  a  repair  can  be  made  by  "  cold-soldering" —  see  Tech- 
nicals —  which  will  be  so  serviceable  as  to  probably  be  in  good 
order  as  long  as  any  other  portion  of  the  filling,  and  it  can  be 
done  with  perfect  facility,  with  comfort  to  the  patient,  and  in 
ten  or  fifteen  minutes. 

If  a  large,  strong  molar  has  been  handsomely  and  perma- 
nently—  accidents  aside  —  filled  with  gold,  and,  as  the  result 
of  a  tremendous  bite,  the  whole  buccal  face  of  the  tooth  has  been 
fractured  off,  a  repair  of  gold  would  be  far  more  tedious,  far 
more  difficult,  and  far  more  expensive  than  was  the  original 
filling.  "With  contour  amalgam,  this  repair  would  be,  com- 
paratively, but  a  trifle.  It  would  take  no  more  time  than 
would  an  ordinary  filling ;  it  would  be  done  without  physical 
tax  to  either  operator  or  patient,  and  would  be  far  less  expen- 
sive than  was  the  filling  to  which  it  would  be  built  on. 

If  small  pieces  of  tooth  are  fractured,  an  opportunity  for 
making,  of  the  remaining  filling,  a  bi-metallic,  is  offered.  This 
is  done  so  nicely,  with  such  celerity,  and  with  so  little  cost,  as 
to  most  favorably  impress  patients  with  the  working  of  plastic 
dentistry,  and  thus,  by  "  little  things,"  prepare  them  for  continu- 
ances of  relief  from  infliction,  until  they  f  re  shown  that  the 
resources  are  almost  endless,  and  until  they  know,  "of  their 
own  knowing/'  that  good,  substantial,  compensating  dentistry 
is  not  necessarily  attended  with  the  non-compensating  inflic- 
tions to  which  they  had  been,  for  years,  subjected. 

Split  Teeth. —  For  more  than  thirty  years,  attempts  have  been 
successfully  made  at  rendering  teeth,  which  had  been  split 
throuo-h  the  roots,  useful  bv  "  bolting."  The  making  of  the 

o  ,*  o  o 

gold  bolt  with  its  screw  and  burr;  the  countersinking  and 
covering  of  the  screw-head  by  filling;  the  after  preparation 
and  the  final  filling  of  the  split  root  and  tooth  with  gold,  con- 
stituted a  series  of  manipulations  which  made  the  operation 
difficult,  delicate,  and  very  expensive.  All  this  is  changed ; 
and,  although  the  work  as  now  done  with  amalgam  could  be 
done  with  gold,  and  beautifully  done,  and  could  not  be  done 
nearly  so  well  with  the  amalgams  almost  universally  employed, 


136  PLASTICS     AND     PLASTIC    FILLING. 

it  can  yet  be  better  done,  taking  everything  into  consideration, 
by  the  "  amalgam  method "  of  the  present  day  than  by  any 
other  way. 

If  the  split  tooth  contains  a  vital  pulp,  the  devitalization  of 
this  is  the  first  thing  to  be  done.  The  parts  are  gently  drawn 
into  apposition  by  means  of  book-binder's  thread  passed  around 
the  neck  of  the  tooth,  and  an  application  is  carefully  punctured 
into  the  pulp.  This  application  should  be  very  small  in  quan- 
tity and  should  be  largely  acetate  of  morphia  paste. 

If  possible,  it  should  be  only  this,  and  especially  for  the  bul- 
bous portion  of  the  pulp,  and  if  the  arsenical  application  i,< 
found  necessary,  it  should  be  made  as  intimately  mixed  with 
cotton  wool  as  possible,  instead  of  being  introduced  looselv  in 
paste  form.  The  "  devitalizing  fibre "  is  admirably  adapted 
for  this  purpose,  to  be  used  in  very  minute  pieces.  It  must  be 
remembered  that  the  split  is  a  direct  route  to  the  peridentium, 
and  that  the  least  arsenical  impress  upon  that  membrane  at  so 
high  a  point  will  probably  eventuate  in  death  of  the  tooth,  and 
will  be  naturally  followed  by  exfoliation. 

The  pulp  having  been  devitalized,  the  tooth  is  placed  in  the 
same  category  with  all  split  pulpless  teeth,  for  which  the  first 
indication  is  the  accurate  joining  together  of  the  parts.  This 
is  accomplished  by  ligating  at  the  neck  with  book-binder's 
thread,  drawing  it  as  firmly  as  is  consistent  with  comfort,  and 
having  the  knot  held  by  pressure  from  a  suitably  shaped  ser- 
rated plugger,  until  it  is  securely  tied.  The  thread  should  then 
be  allowed  to  shrink  from  moisture,  and  in  ten  or  fifteen  minutes 
a  second  ligature  should  be  tied  as  firmly  as  possible  either 
above  or  below  the  first  ligature.  The  position  of  the  second 
ligature  is  decided  by  the  manner  in  which  the  parts  draw  to- 
gether. The  second  ligature  should  then  be  allowed  to  shrink, 
when  a  third  ligature  should  replace  the  first  one,  or  be  passed 
around  the  tooth  on  the  opposite  side  of  it  from  the  second  one. 

The  objects  which  must  be  gained  by  the  ligatiou  are.  first, 
the  accurate  placing  of  the  parts  in  apposition,  and,  second,  the 
firm  maintenance  of  this  condition.  The  tooth  is  then  care- 
fully entered  by  drilling ;  the  pulp  cavity  is  cleansed,  and  the 
canals  —  enlarged  by  Talbot  reamers — are,  if  possible,  utilized 
for  effecting  the  reparation.  In  first  bicuspids  and  upper  nnd 


GENERAL    CO  XS  I  DERATIONS.  137 

lower  molars,  these  are  generally  available,  but  in  single  rooted 
teeth  the  uniting  drillings  have  to  be  made  according  to  cir- 
cumstances. The  principle  of  securing  is  by  "  dumb-bell "  or 
"double-headed"  union;  a  drill-hole  is  made  in  each  portion 
uf  split  root,  or  the  canals  are  enlarged  in  bi-rooted  or  multi- 
rooted  teeth;  these  large,  round  drill-holes  are  then  united  by 
narrow  fissure-drilled  canals.  The  cracks  of  fracture  are 
opened  from  the  pulp-cavity  almost  to  the  periphery,  and  then 
the  drill-holes,  fissured  canals,  and  cracks  of  fracture  are  all 
filled  with  contour  amalgam.  It  is  sometimes  possible  to  add 
dove-tails  cut  in  the  crown  portions  of  the  teeth,  but,  if  this  is 
not  practicable,  drill-pits  should  be  made  in  the  substance  of 
each  part,  and  these  should  be  enlarged  into  spheroids,  that 
thus  increased  strength  of  union  be  given  to  this  part  of  the 
filling.  If  there  is  not  substance  sufficient  for  this  in  conse- 
quence of  previous  extended  decay,  drill-holes  should  be  made 
completely  through  the  enamel ;  these  should  be  countersunk 
upon  the  enamel  surface,  and  thus  "rivet-head"  fillings  be 
made. 

From  what  has  already  been  said,  it  will  be  at  once  suggested 
that  crown-linings  and  rivet-heads  exposed  to  view  should  be 
made  of  facing  amalgam,  while  all  the  other  filling  should  be 
of  contour  amalgam. 

I  have  quite  a  number  of  these  operations  in  hard  service, 
many  of  which  have  been  doing  duty  for  from  one  to  nearly 
five  years,  and,  as  a  rule,  they  have  thus  far  been  more  satis- 
factory than  the  "  bolted "  operations,  though  some  of  these 
have  done  remarkably  well;  but  the  decided  advantages  of  the 
amalgam  "joining"  are  the  greater  facility  with  which  the 
work  is  done ;  the  almost  complete  avoidance  of  irritation  dur- 
ing dental  manipulation,  and  the  reduction  of  expense  to  one- 
half,  and  in  large  cases  to  one-quarter  that  of  the  "gold  bolt" 
operation ;  while  the  compensation  for  time  of  operator  is 
equally  great  and  the  comfort  and  satisfaction  to  the  patient  are 
increased. 

The  ligatures  should  remain  on  the  tooth  for  a  day  or  two,  if 
there  is  no  gum  irritation  from  them ;  but  if  that  one  nearest 
the  gum  irritates,  it  should  be  removed  upon  completion  of 
operation.  In  a  couple  of  days  the  ligatures  should  be  cut  off, 


138  PLASTICS     AND     PLASTIC     FILLING. 

and  any  finishing  which  may  be  required  in  parts  covered  by 
them,  should  be  looked  for  and  done. 

Perforated  Teeth. —  These  are  teeth  in  which  decay  has  so 
progressed,  or  in  which  drilling  or  excavating  has  been  carried 
so  far,  as  to  have  made  an  opening  through  the  cementum  ;  they 
are  frequently  regarded  as  not  amenable  to  treatment,  or,  if 
attempted,  are  usually  considered  as  extraordinary  in  the  line 
of  dental  manipulation.  A  trial  of  some  such  cases,  with  plas- 
tic fillings,  will  soon  make  of  them,  to  all  practitioners,  that 
which  they  are  to  the  plastic  workers,  viz.,  matters  of  very  little 
moment.  Cotton  wool,  saturated  with  oil  of  cloves,  is  pressed 
gently  into  the  cavity,  and  iillowed  to  impinge  upon  outside 
tissue  just  sufficiently  to  permit  an  accurate  contour  healing  — 
neither  concave  nor  convex.  The  cavity  being  then  very  gently 
dried  with  absorbent  cotton,  a  smooth  piece  of  lov:-heat  gutta- 
percha —  white  —  is  laid  over  the  orifice  and  secured  in  position 
by  accurate  pressure  —  oiled  instruments,  cold  —  against  the 
edges.  This  is  then  firmly  fixed  by  submarine  amalgam  —  soft 
mix  —  with  which  all  the  floor  of  the  cavity  is  covered.  This 
removes  all  "perforation"  complication,  and  reduces  the  work 
to  ordinary,  with  the  exception  of  regard  for  possible  future 
contingencies.  If  the  perforation  is  very  large,  the  tooth  in 
the  lower  jaw,  and  the  patient  of  strumous  or  otherwise  doubt- 
ful diathesis,  all  arrangements  for  occasional  vent,  if  required, 
should  be  made,  though  my  experience  is,  that  the  "extraor- 
dinary "  concomitants  of  these  cases  are  the  ease  with  which 
they  are  generally  treated,  and  the  equanimity  with  which  the 
surrounding  tissues  accept  the  conditions. 

Loose  and  divided  Roots. —  We  have  now  arrived  at  what  may 
be  regarded  as  the  great  dividing  line  between  gold  and  plastic 
dentistry. 

Up  to  this  point,  the  gold- worker  is  able  to  do,  after  a  fash- 
ion, all  that  can  be  so  effectually  accomplished,  so  much  more 
easily,  with  plastics;  but  now  the  limit  has  been  reached.  We 
here  enter  upon  a  broad  field  of  impossibilities  to  the  gold- 
\vorker,  and  yet  a  field  in  which  the  marvels  of  plastics  seem 
fairly  to  revel. 

A  patient  applies,  who,  having  lost  nearly  all  the  teeth,  has 
worn  a  partial  denture  clasped  to  bicuspids.  One  of  these  has 


GENERAL,    CONSIDERATIONS.  139 

gradually  loosened,  and  has  finally  dropped  out.  The  roots  of 
an  adjoining  molar,  quite  loose  and  decidedly  doubtful,  the 
palatal  separated  from  the  buccal,  are  each  drilled  out,  and 
"ring-bolts"  of  platinum  wire  —  made  by  rivet-heading  one 
end,  and  forming,  by  round-jawed  pliers,  a  ring  upon  the 
other  end  —  are  filled  into  them.  These  fillings  having  set, 
the  roots  are  drawn  together  by  a  ligature  passed  through  the 
rings.  When  they  are  fairly  in  apposition,  a  foundation  of 
submarine  amalgam  is  made,  resting  upon  the  roots,  and  held 
between  the  bolts.  This  is  allowed  to  set  thoroughly,  when 
contour  amalgam  is  built  up  domelike  to  the  ligature,  entering 
into  the  rings  and  securely  binding  the  whole  together.  After 
this  has  hardened,  the  ligature  is  cut  off,  a  clasp  is  approxi- 
mately adjusted  and  soldered  on  to  the  work ;  a  bicuspid  is 
also  added,  and  the  piece  is  placed  in  position  ;  then,  with 
contour  amalgam,  a  nice  crown  is  readily  built  on,  fitting  the 
clasp  to  perfection,  from  the  cervical  edge  of  the  previous 
dome-like  building  down  to  the  now  entirely  covered  tops 
of  the  ring-bolts. 

This  soon  sets,  the  work  is  carefully  removed,  any  defect  of 
filling  is  made  perfect  by  additions  of  amalgam,  and  the  crown 
is  smoothly  finished  off.  In  an  hour  this  can  be  used  with 
safety,  and,  as  the  result  of  such  work,  the  patient  is  made 
"more  comfortable  than  ever  before."  So  he  said. 

A  patient  applies  who  has  but  two  teeth  left  on  either  side 
for  mastication  ;  one  of  these,  a  lower  molar,  has  recently  been 
broken,  and,  in  the  fracture,  the  distal  half  of  the  crown, 
with  a  large  and  very  expensive  filling,  has  been  broken  oft', 
and  the  distal  root  split  apart  from  the  remaining  crown  and 
root.  In  a  few  days  the  separation  between  the  roots  became 
enlarged  from  the  forcing  of  food  during  attempts  at  mastica- 
tion upon  the  half-crown,  and  such  soreness  supervened  as  to 
preclude  further  effort  upon  that  side.  The  other  side  has 
given  such  decided  evidence  of  trouble,  from  its  constant  use 
for  a  week,  that  relief  is  sought.  A  ring-bolt  is  filled  into  the 
distal  root ;  the  canals  of  the  mesial  root  are  widely  opened 
for  retaining  hold ;  and,  a  large  drill-hole  having  been  made 
through  the  mesial  face  of  the  half-crown,  it  is  well  counter- 
sunk from  the  outside.  The  distal  root  is  drawn  back  into 


140  PLASTICS    AND    PLASTIC    FILLING. 

position  by  a  ligature  passed  through  the  drill-hole  and  around 
the  bolt.  A  foundation  is  made  of  submarine  which  connects 
the  bolted  root  with  the  mesial  half,  held  by  the  canal  hold ; 
when  this  is  hardened,  the  ligature  is  taken  off  and  a  contour 
crown  is  built  on,  around,  and  through  the  ring-bolt  and  through 
the  mesial  drill-hole,  and  is  rivet-headed  in  the  countersink. 

This  has  been  eaten  on,  most  satisfactorily,  for  several  years. 

A  patient  applies,  nearly  seventy  years  of  age,  who  has  lost  all 
teeth  except  the  superior  and  inferior  incisors  and  'cuspids,  and 
these  are  worn  almost  to  the  gum.  The  left  lower  second  molar 
has  advanced  quite  to  the  position  formerly  occupied  by  the 
first  molar.  A  crown  has  just  been  lost  from  the  upper  jaw, 
which,  though  rather  loose,  has  subserved  the  purposes  of  mas- 
tication "  much  better  than  nothing."  It  is  shown,  and  is  found 
to  be  the  crown  of  the  upper  second  molar  which  had  decayed 
from  the  palatal  and  mesio-buccal  roots,  which  had  gradually 
loosened  and  come  away.  Another  root,  the  disto-buccal  of  the 
first  molar,  is  in  position.  These  three  distinct  and  separated 
roots  of  two  teeth  are  drawn  together  and  utilized  by  crowning, 
and  the  patient  is  "  glad  the  old  tooth  came  out ;  "  for  he  eats 
"  so  much  better  with  the  new  one." 

A  patient  applies  whose  eating  has  been  done,  for  a  number 
of  years,  by  two  molars  of  the  right  side  and  by  two  first  bi- 
cuspids of  the  left  side.  There  are  no  other  teeth  or  roots 
on  the  right  side ;  but  there  is  the  second  superior  bicuspid  of 
the  left  side,  the  root  of  the  second  inferior  bicuspid  —  loose, 
—  and  a  lower  molar  root,  quite  near  to  it  and  quite  firmly 
implanted. 

The  crown  has  recently  been  broken  from  the  first  inferior 
bicuspid,  and,  the  eating  having  necessarily  been  done  exclu- 
sively upon  the  right  side,  the  two  molars  have  begun  to  com- 
plain. The  three  roots  are  ring-bolted,  and  a  long,  continuous 
crown  is  built  upon  the  three.  The  two  firm  roots  hold  the 
middle  loose  one  strongly  in  place,  and  both  the  bicus2)ids  of  the 
left  superior  jaw  are  utilized.  Ample  masticating  surface  is 
thus  given,  and  the  patient  relieved  from  the  burden  of  arti- 
ficial work. 

It  is  needless  to  multiply  cases,  for  these  will  suffice  to  dem- 
onstrate how  it  is  that  the  plastic- worker  can  take  the  wrecks 


GUTTA-PERCHA.  141 

alike  from  gold- work  and  from  neglect,  and  make  the  patients 
"  rejoice  and  be  glad  "  at  a  time  of  life  when  they  have  come 
to  realize  the  impossibility  of  enduring  further  infliction,  the 
folly  of  continuing  needless  neglect,  and  the  almost  boundless 
signification  of  the  phrase,  "  comfort  from  plastics" 


AETICLE  XIII. 
G  UTTA-PEE  CHA . 

THIS  material  was  offered  for  dental  consideration  about 
thirty  years  ago. 

It  was  suggested  as  a  temporary  stopping  for  frail  teeth,  and 
was  recommended  for  its  ease  of  manipulation ;  its  non-irrita- 
ting and  non-conducting  qualities ;  its  insolubility  in  the  fluids 
of  the  mouth,  and  its  reasonable  resistance  to  attrition. 

These  desirable  characteristics  caused  it  to  find  favor  in  a 
limited  degree,  even  though  its  color  —  a  dark  brown  —  was 
very  objectionable ;  but,  upon  the  introduction  of  a  mixture 
known  as  "Hill's  Stopping,"  and  supposed  to  be  composed  of 
gutta-percha,  quicklime,  and  pulverized  silex  (a  supposition 
probably  entirely  erroneous),  it  was  quite  promptly  accepted 
with  marked  favor,  and  soon  took  position  as  a  very  valuable 
adjunct  in  practice. 

Its  inventor,  Dr.  Hill,  had  quite  exalted  ideas  of  the  value 
of  his  invention,  for  he  stated  that  while  he  did  "  not  expect  it 
to  supersede  gold  entirely,"  he  nevertheless  believed  that  it 
could  be  "  advantageously  substituted  for  that  material  in  many 
instances." 

The  advocates  of  the  "  compatibility  theory  "  believe,  at  the 
present  day,  that  his  views  were  correct,  and  that  if  they  had 
been  very  much  more  universally  accepted,  the  result  would 
have  been  a  vastly  better  record  in  the  saving  of  teeth. 

Other  compounds,  of  a  like  nature,  were  soon  introduced  as 
"superior,"  but  with  little  or  no  just  claims  to  such  distinction, 
as,  after  trying  a  great  variety  of  ingredients  for  the  purpose 
of  whitening  the  gutta-percha  without  seriously  impairing  its 
toughness,  nearly  all  the  better  grades  were,  and  are,  composed 
mainly  of  /jutta-percha  and  oxide  of  zinc. 


142  PLASTICS    AND    PLASTIC    FILLING. 

Like  other  manufactured  articles,  it  was  soon  found  that 
much  more  depended  upon  the  art  of  manufacture  than  upon  the 
components  of  the  filling  material,  and  at  present  the  relative 
quality  of  the  various  "  makes  "  is  due  largely  to  this. 

Early  in  the  use  of  gutta-percha  stoppings  it  was  noticed 
that  "remarkable  results"  were  being  attained,  and  those  who 
were  investigating  these  with  a  view  to  the  future  modification 
of  practice  came  in  due  time  to  regard  them  with  exceeding 
favor. 

It  was  gradually  accepted  that  gutta-percha  had  its  place  not 
only  as  a  "temporary  filling,"  but  as  a  stopping  of  extraordinary 
permanency,  having  but  two  demerits  of  note,  viz. :  inability  to 
resist  the  attrition  of  mastication,  and  a  degree  of  shrinkage 
which  permitted  leakage  and  a  consequent  "  clouding  "  of  the 
filled  tooth. 

The  first  of  these  objections  was  only  to  be  overcome — in  the 
use  of  the  one  material  —  by  restricting  its  employment  to  such 
cavities  as  were  so  situated  that  but  little  or  no  attrition  would 
result  from  mastication,  and  by  directing  especial  avoidance  of 
friction  from  the  brush  during  the  cleansing  of  the  teeth. 

The  second  objection  was  by  no  means  so  easily  disposed  of. 
In  fact,  after  much  thought  and  experimentation,  it  has  been 
found  practically  insurmountable. 

Solutions  of  gutta-percha  were  tried  as  "linings"  for  cavities 
more  than  twenty  years  ago,  but  the  shrinkage  from  evapora- 
tion was  proved  to  be  even  worse  than  that  from  cooling,  and, 
as  it  was  indispensable  that  the  material  should  be  heated  in 
order  to  be  properly  introduced,  it  was  finally  announced  that 
the  best  gutta-percha  fillings  leaked,  but  that  this  leakage  was 
not  detrimental  except  so  far  as  it  permitted  slight  discoloration. 

The  gutta-percha  filling  materials  of  the  present  day  are  di- 
vided into  three  grades : 

First.  Those  of  "low  heat," — having  sufficient  plasticity 
for  manipulation  at  temperatures  ranging  from  140°  to  200° 
Fah. 

These  are  always  to  be  warmed  over  water,  and  are  particu- 
larly applicable  for  filling  portions  of  canals  and  the  bulbous 
parts  of  pulp-cavities ;  and  for  covering  almost-exposed  pulps 
to  prevent  danger  from  irritating  medicaments  employed  as  ob- 


GUTTA-PERCHA.  143 

tundents  for  sensitive  dentine  ;  and  as  a  first  layer  of  filling  in 
"deep-seated"  cavities  of  decay.  They  should  be  worked  with 
bulbous  or  serrated  instruments,  cold  and  oiled. 

They  should  not  be  used  for  "outside  work,"  as  their  resist- 
ance to  attrition  is  quite  moderate. 

I  refer  here  exclusively  to  "low  grade"  white  gutta-perchas, 
for  it  is  never  the  case  that  red  gutta-percha  base-plate  (a  very 
useful  and  eminently  serviceable  filling  material)  is  of  higher 
grade  than  150°  or  180°  Fah. 

Second.  Those  of  "medium"  grade, — such  as  become  plastic 
at  temperatures  ranging  from  200°  to  210°  Fah. 

In  my  opinion,  these  are  the  best  gutta-perchas  for  general 
use,  for  the  various  reasons  that  they  can  be  warmed  over 
water,  thus  insuring  against  "heat-rotting"  from  overheating; 
that  by  this  means  they  arc  prevented  from  being  injured  from 
repeated  heating,  and  that  they  possess  sufficient  consistence, 
toughness,  and  resisting  capacity  to  subserve  the  purposes  of  an 
excellent  and  durable  filling. 

Third.  Those  of  "high  heat," — which  do  not  become  suf- 
ficiently plastic  for  manipulation  at  less  than  from  216°  to  230° 
Fah. 

As  these  will  not  soften  over  boiling  water,  they  have  to  be 
heated  upon  a  metal  or  porcelain  plate,  or  over  the  flame  of  a 
spirit-lamp.  This  requires  much  care,  as  it  is  essential  to  good 
results  that  they  be  very  gradually  heated  lest  they  suddenly 
swell  and  deteriorate,  and  that  they  be  not  overheated,  as  then 
they  disintegrate  and  become  "heat-rotted." 

Much  of  the  obloquy  which  has  attached  to  gutta-percha 
work  has  unquestionably  been  due  to  ignorance  of  these  facts, 
and  to  consequent  mismanagement  of  the  material ;  and  I  have 
never  yet  conversed  with  any  gentleman  that  denied  the  per- 
manency of  gutta-percha  fillings  who  did  not  heat  his  filling 
material  either  upon  a  plate  of  porcelain  or  metal,  or,  worse 
yet,  over  the  flame  of  the  spirit-lamp. 

I  would  state  here  that  the  value  of  gutta-percha  stopping  is 
not  to  be  determined  alone  by  the  "heat-test,"  for  it  is  easy  to 
raise  the  material  to  any  reasonable  deyree  by  simply  increasing 
the  relative  quantity  of  inorganic  admixture,  but  this  very  in- 
crease is  destructive  to  value  by  overloading  the  gutta-percha. 


144  PLASTICS    AND    PLASTIC    FILLING. 

All  other  things  being  equal,  that  gutta-percha  stopping  which 
gives  the  highest  heat-test  with  the  least  admixture  of  foreign  ma- 
terial is  the  best. 

Although  gutta-percha  has  been  proved  to  make  a  reason- 
ably good  stopping  in  cavities  from  which  it  was  found  impos- 
sible to  exclude  the  moisture,  it  is  nevertheless  essential  to  as 
perfect  a  filling  as  can  be  introduced  that  dry  ness  be  maintained 
during  its  introduction. 

If  this  is  not  possible,  I  should  recommend  the  employment 
of  the  red  base-plate  in  preference  to  any  preparation  of  white 
stopping,  warming  it  over  water,  and  using  cold  instruments  for 
its  introduction,  which  should  be  touched  to  an  oil-pad  to  pre- 
vent adhesion  of  instrument  and  consequent  "drawing"  of  fill- 
ing material. 

NOTE. —  The  oil-pad  is  conveniently  made  by  cutting  a  groove  with  a  small  co- 
rundum wheel,  around  the  end  of  any  ordinary  flat  top  glass  stopper,  and  then, 
stretching  a  piece  of  chamois-skin  over  the  end,  securing  it  by  a  ligature  of  book- 
binder's thread  in  the  groove. 

After  properly  trimming  the  chamois-skin,  a  drop  or  two  of  sewing-machine 
oil  saturates  it,  and  it  is  ready  for  use. 

This  little  device  is  essential  not  only  in  gutta-percha  work,  but  in  connection 
with  the  manipulation  of  the  zinc-phosphates  also. 

In  all  cases  where  dryness  can  be  maintained,  I  should  prefer 
to  use  the  medium  heat  white  preparations.  These  should  in- 
variably be  introduced  by  means  of  warm  instruments,  as  the 
necessary  degree  of  heat  for  deliberate  and  accurate  manipulation 
can  only  be  retained  to  the  gutta-percha  in  this  manner.  For 
this  purpose  a  combined  gutta-percha  and  instrument -warmer, 
of  any  desirable  pattern,  should  be  used. 

The  gutta-percha  should  be  heated  either  over  water  ("  low 
heat"  or  "medium")  or  upon  a  metal  plate  ("high  heat"  only), 
but  the  instruments  should  always  be  heated  upon  a  metal  plate, 
—  this  insures  that  they  shall  be  hotter  than  the  gutta-percha, 
and  thus  that  they  shall  be  as  warm  when  taken  from  the  plate 
and  carried  to  the  mouth  as  was  the  gutta-percha  when  taken 
from  its  place  over  the  water-bath. 

Another  advantage,  and  a  very  great  one,  which  is  attained 
by  an  instrument-warmer,  is  the  ability  to  heat  at  one  time  all 
the  various  instruments  required  in  any  given  operation ;  this 


GUTTA-PERCHA.  145 

will  be  found  quite  desirable,  and  to  result  in  a  great  saving  of 
time. 

Again,  instruments  heated  in  a  flame  are  very  liable  to  leave 
traces  of  soot  upon  the  filling,  while  'those  heated  upon  a  plate 
always  leave  it  in  a  neat  and  presentable  condition. 

The  instruments  best  adapted  for  the  introduction  of  gutta- 
percha  fillings  are  —  with  the  occasional  exception  of  a  ball- 
burnisher  —  certain  forms  of  those  used  for  the  manipulation 
of  cohesive  foil. 

It  is  important,  however,  to  note  that  instruments  intended 
especially  to  consolidate  gold  foil  by  the  force  of  "  direct  im- 
pact "  are  least  of  all  indicated  for  use  in  the  introduction  of  a 
gutta-percha  filling,  for  the  principles  ivhich  govern  the  durability 
and  value  of  a  foil  filling  are  precisely  opposite  to  those  which 
govern  the  durability  and  value  of  gutta-percha  fillings. 

For  the  perfect  introduction  and  consolidation  of  foil  it  is 
essential  that  free  and  fair  ingress  to  the  cavity  shall  be  obtained, 
and  for  this  purpose  it  is  frequently  necessary  to  cut  away  con- 
siderable portions  of  both  enamel  and  dentine. 

For  the  integrity  of  foil  fillings  it  is  regarded  as  better  that 
the  walls  of  the  cavities  should  possess  a  reasonable  degree  of 
both  thickness  and  strength. 

On  the  contrary,  for  the  perfect  introduction  and  compacting 
of  gutta-percha,  it  is  not  essential  that  nearly  so  free  ingress  to 
the  cavity  should  be  obtained,  while  it  is  essential  that  the 
largest  possible  portion  of  both  enamel  and  dentine  should  be 
carefully  conserved. 

The  most  important  of  this  tooth-tissue  is  just  that  which 
should  be  cut  away  for  foil-work,  and  upon  the  preservation  of 
this  depends,  almost  entirely,  the  value  of  the  gutta-percha 
work,  as  it  guards  against  attrition,  a  material  which,  while  it  is 
eminently  more  tooth-preserving  than  gold,  is  wanting  in  the 
physical  characteristic  of  resistance  to  mastication. 

Again,  for  the  integrity  of  gutta-percha  fillings,  it  is  not  re- 
garded as  important  that  the  walls  of  cavities  should  possess, 
in  much  degree,  cither  thickness  or  strength,  as  it  has  been 
thoroughly  demonstrated  that  some  of  the  most  signal  triumphs 
of  gutta-percha  have  been  in"  teeth  in  which  gold  fillings  of 
magnificent  workmanship  had  failed  repeatedly,  until  the 
10 


146  PLASTICS    AXD    PLASTIC    FILLING. 

remaining  walls  of  the  now  enormous  cavities  were  almost  as 
thin  and  frail  as  letter-paper  ! 

Therefore  serrated  points  of  such  curves  and  angles  as  have 
been  found  best  to  meet  the  requirements  in  difficult  and  inac- 
cessible cavities  are  those  recommended  for  the  introduction  of 
gutta-percha  fillings. 

The  instruments  best  adapted  for  finishing  gutta-percha  fill- 
ings are  thick  and  thin,  convex  or  flat  burnishers;  these,  to- 
gether with  the  occasional  use  of  a  large  or  small  ball-burnisher, 
will  be  found  to  meet  all  requirements.  These  should  be  heated 
in  the  same  manner  as  are  the  pluggers. 

The  filling  material  and  instruments  (both  plugging  and 
finishing)  being  properly  warmed,  the  gutta-percha  should  be 
taken  in  small  pieces  —  piece  by  piece — from  its  plate  by  means 
of  a  moderately  fine  probe,  and  thus  carried  to  the  cavity  and 
placed  in  position.  If  practicable,  each  piece  should  be  made 
to  adhere  to  the  wall  of  the  cavity,  and  then  be  accurately 
packed  into  position  by  the  appropriate  plugger,  until  the  cav- 
ity is  either  entirely  lined,  or  is  partly  filled,  when  the  com- 
pletion of  the  operation  is  only  a  question  of  a  short  time  ;  but 
when  this  adhesion  of  the  first  pieces  is  difficult,  they  should 
be  held  in  position  by  the  probe  until  they  are  made  to  adhere 
to  the  walls  bv  the  use  of  a  plugger,  when  that  adhesion  should, 
in  turn,  be  maintained  by  the  plugger,  while  the  probe  is  care- 
fully withdrawn. 

It  is  an  important  consideration  that  accuracy  in  amount  ©f 
filling  material  should  be  regarded,  as  thus  the  minimum  of 
surplus  will  remain  for  removal  prior  to  finishing. 

During  the  removal  of  surplus  material,  and  the  final  smooth- 
ing of  the  filling,  it  should  always  be  remembered  that  the 
work  must  be  towards  the  edges  of  the  cavity,  as  thus  the  filling 
is  maintained  "flush"  and  the  gutta-percha  kept  close  to  the 
walls. 

While  finishing,  it  will  be  found  that  moisture  is  not  only 
not  detrimental,  but  in  some  cases  rather  advantageous,  as  it  per- 
mits a  smoother  cutting  of  the  gutta-percha. 

In  dry  finishing,  only  that  portion  of  the  filling  material 
which  will  adhere  to  the  instrument  from  one  touch  should  be 


GUTTA-PERCHA.  147 

removed  at  a  time,  as  retouching  will  complicate  and  retard 
progress  rather  than  be  productive  of  advance. 

Tests  for  Gfutta-Percha  Stopping. —  As  there  are  very  numer- 
ous "  makes  "  of  gutta-percha,  and  as  some  of  these,  least  wor- 
thy of  confidence  as  filling  material,  are  advertised  as  "  the  very 
best "  of  their  kind,  I  deem  it  important  that  reliable  tests  for 
this  valuable  aid  in  saving  teeth  shall  not  be  wanting,  that  thus 
with  care  in  heating,  and  with  proper  working,  the  excellent 
results  which  are  possible  \vitli  a  <jood  material  may  not  only  be 
confidently  anticipated,  but  fully  realized. 

First.  Heat-Test.  —  For  the  accurate  establishment  of  the 
"  grade  "  of  any  given  sample  of  gutta-percha,  it  is,  of  course, 
necessary  to  employ  a  "heat-tester."  The  illustration  suffi- 
ciently explains  itself,  as  the  instrument  is,  practically,  a  gutta- 
percha  warmer  with  thermometer  attached.  A  sufficiently  ac- 
curate arrangement  can  be  made  by  taking  any  small  tin  box, — 
such,  for  instance,  as  are  bought  with  spices, —  and  cutting  an 
opening  in  the  cover  sufficiently  large  to  permit  the  intro- 
duction of  a  thermometer.  It  should  then  be  partially  filled 
with  water  and  arranged  for  gradual  heating. 

The  thermometer  should  register  at  least  212°  F.,  while  that 
used  for  the  instrument  illustrated  registers  230°.  No  gutta- 
percha  can  be  serviceably  worked  which  grades  higher  than 
220°,  and  I  regard  this  as  uselessly  high.  At  240°,  gntta-percha 
"heat-rots,"  and  does  not  regain  its  previous  toughness  or  in- 
tegrity, and  if  at  208°  or  209°  it  softens  sufficiently  for  easy 
manipulation,  it  is,  if  properly  constituted,  sufficiently  resistant 
to  respond  to  all  the  legitimate  requirements  of  a  good  gutta- 
percha  filling  material. 

But,  as  I  have  said,  the  value  of  gutta-percha  stopping  is  not 
to  be  determined  by  the  heat-test  alone,  for  it  is  easy  to  raise  it 
to  the  proper  "grade-test"  by  addition  of  inorganic  constit- 
uents. To  further  determine  its  value,  then,  it  is  necessary  to 
decide  upon  the  relative  quantities  of  organic  and  inorganic 
constituents ;  for  this  we  have  the  "  fire-test." 

Second.  Fire-Test. —  This  is  done  by  weighing  a  small  quan- 
tity—  say,  a  pennyweight  —  which  it  is  better  should  be  in  one 
piece.  This  is  then  subjected  to  high  heat ;  a  convenient 
method  is  to  place  it  upon  a  long-handled  iron  spoon,  and  put 


148  PLASTICS    AND     PLASTIC     FILLING. 

it  on  a  hot  fire  ;  in  a  few  minutes  it  takes  fire ;  burns  with  a 
bright  blaze ;  ceases  to  burn ;  becomes  red  hot  and  thoroughly 
calcined,  while  it  perfectly  retains  its  original  shape.  It  should 
then  be  allowed  to  cool,  after  which  the  residuum  should  be 
carefully  weighed. 

If  one  pennyweight  of  gutta-percha  stopping  has  been  thus 
treated,  the  residuum  should  weigh  a  little  over  nineteen  grains 
if  the  inorganic  constituent  is  oxide  of  zinc  and  the  gutta- 
percha  stopping  of  "  low-heat  "  grade  —  1  part  G.  P.  to  4  parts 
o.  z.  If  the  pennyweight  tested  is  "  medium  heat,"  and  is 
properly  and  toughly  plastic  at  209°,  the  residuum  —  if  oxide 
of  zinc — should  weigh  twenty  or  twenty-one  grains  —  1  part 
G.  P.  to  6  or  7  parts  o.  z. 

/  refer  to  these  proportions  and  ingredients  because  a  THOROUGH 
KNEADING  of  them  upon  an  iron  or  porcelain  slab  at  a  moderate 
heat — over  boiling  water  —  will  produce  an  excellent  filling  ma- 
terial of  the  two  most  desirable  grades.  The  gutta-percha  to  be 
used  is  that  which  is  sold  in  large,  dark-brown  sheets,  resem- 
bling dark  sole-leather,  and  not  that  which  is  light  colored,  and 
either  in  thick  pieces  or  thin  paper-like  sheets. 

For  making  of  a  small  quantity  of  gutta-percha  stopping  — 
one  to  four  or  five  ounces  —  it  is  needed  that  a  vessel  be  ar- 
.  ranged  for  the  boiling  of  water.  Upon  this  is  placed  a  cover 
of  tin,  iron,  or  porcelain  —  a  tin  cover  with  druggist's  slab  is 
appropriate  —  with  a  tube  for  escaping  steam.  Upon  the  slab 
or  cover  is  placed  the  gutta-percha  and  a  portion  of  the  oxide 
of  zinc.  As  soon  as  the  gutta-percha  softens,  the  zinc  powder 
is  gradually  kneaded  into  it.  In  my  experience,  this  is  best 
done  by  means  of  a  small  wedge-shaped  tool  of  iron  —  very- 
blunt —  set  into  a  small  chisel  handle,  turning  the  mass  with  a 
short,  stiff  spatula.  The  incorporation  of  the  zinc  should  always 
be  in  consonance  with  the  maintenance  of  the  toughness  of  the 
gutta-percha  —  never  faster  —  and,  after  the  zinc  is  all  incorpo- 
rated^ the  mass  should  be  thoroughly  kneaded  for  an  hour  or 
more,  until  the  stopping  is  perfectly  toughened. 

It  is  possible  that  better  —  tougher  —  gutta-percha  stoppings 
may  be  devised  in  the  future,  but  all  unfounded  pretensions  in 
that  direction  may  easily  be  detected  by  the  tests  given ;  mean- 
while, those  which  are  made  from  the  formulas,  and  by  the 


GUTTA-PERCHA.  149 

method  given,  will  be  found  reliable,  as  they  have  been 
"  placed  "  by  the  results  of  twenty  years  of  experiment,  during 
which  time  the  inferior  stoppings  that  have  too  generally  been 
made,  sold,  and  used,  have  given  so  much  dissatisfaction  as  to 
have  caused  the  mass  of  the  profession  to  accept  as  true  the  oft 
repeated  solecism,  that  the  making  of  good  gutta-percha  stop- 
ping is  one  of  the  "lost  arts"  ! 

Durability  of  Gutta-percha. —  It  was  quite  a  number  of  years 
after  the  entrance  of  gutta-percha  into  the  list  of  filling  ma- 
terials before  it  carne  to  be  regarded  by  any  operators  as  other 
than  subservient  for  "  temporary  "  work,  but,  after  a  time,  cases 
began  to  multiply  in  which  fillings  inserted  avowedly  as  "  tem- 
porary "  continued  to  do  good  service  in  such  manner  as  to  ex- 
cite both  curiosity  and  professional  interest  as  to  the  length  of 
their  possible  durability. 

It  was  next  noted,  as  years  passed  by,  that  the  gutta-percha 
fillings  had  actually  lasted,  in  many  instances,  longer  than  the 
gold  fillings  which  had  been  previously  introduced. 

Results  such  as  these,  in  my  own  practice,  together  with  cor- 
roborative comparison  of  views  with  others,  induced  me  to  in- 
stitute an  extended  course  of  experimentation  in  this  direction. 
As  the  result  of  over  fifteen  years  of  careful  observation, 
and  with  a  basis  of  over  two  thousand  replacements  of  gold 
with  gutta-percha,  I  find  that,  "  properly  used,"  gutta-percha  is 
at  least  twice  as  durable  as  gold,  and  that  in  very  soft  teeth, 
in  selected  places,  it  is  fair  to  presume  that  it  will  preserve 
its  tooth  at  least  three  times  as  long  as  well-introduced  gold 
fillings. 

I  wish  it  to  be  understood  by  the  profession  that  I  do  not 
make  this  statement  as  an  opinion,  but  as  an  assertion  vouched 
for  by  long,  carefully  tabulated  records,  and  as  a  basis  upon 
which  the  operators  of  the  future  may  found  a  satisfactory, 
tooth-saving,  and  comfort- giving  practice. 

Cavities  in  which  the  use  of  Gutta-percha  (alone)  is  indicated. 
—  In  former  years,  the  cavities  in  which  experience  seemed  to 
have  conclusively  proved  the  capability  of  gutta-percha  for 
making  a  reliable  tooth-saving  filling  were  much  more  numer- 
ous than  at  present.  At  that  time  all  circumscribed  cavities 
upon  the  mesial  or  distal  faces  of  soft  teeth,  as  well  as  many 


150  PLASTICS    AND     PLASTIC    FILLING. 

cavities  upon  the  labial  faces  of  incisors  and  cuspids  and  buccal 
faces  of  bicuspids,  and  especially  large  cavities  upon  the  buccal 
faces  of  molars  near  to  and  even  beneath  the  gums,  were  re- 
garded by  gutta-percha  workers  as  the  places  where  they 
achieved  their  greatest  triumphs. 

Gradually,  as  "  combination  fillings  "  began  to  be  recognized 
as  advanced  practice,  the  legitimate  use  of  gutta-percha  alone 
has  become  restricted,  first,  to  large  cavities  approaching  the 
pulps,  and  having  thin,  frail  walls  located  upon  the  buccal  faces 
of  molars  and  bicuspids,  either  superior  or  inferior ;  second,  to 
circumscribed  cavities  upon  the  mesial  or  distal  faces  of  inci- 
cuspids,  and  bicuspids  having  reasonably  thick  walls  labially 
"and  bticcally  (sufficiently  so  to  prevent  "  clouding  "  from  leak- 
age^, and  having  an  unbroken  articulating  wall  of  sufficient 
strength  to  resist  the  action  of  mastication. 

In  soft  teeth  all  these  requirements  are  but  infrequently  found, 
and  thus  it  is  that,  at  the  present  day,  the  strictly  legitimate 
use  of  gutta-percha  alone  as  a  filling  material  is  almost  entirely 
confined  to  large  cavities,  having  thin,  frail  icalU,  located  >/j>»/t 
the  buccal  faces  of  molars. 

But  it  is  by  no  means  the  case  that  the  use  of  gutta-percha 
is  confined  to  cavities  in  which  it  alone  is  indicated  as  the  best 
of  all  filling  materials ;  for  its  great  value  as  a  "  guard  "  at  the 
cervical  portion  of  cavities  between  teeth,  and  as  an  "  inter- 
mediate "  between  almost  exposed  pulps  and  amalgam  or  zine- 
phosphate  fillings;  as  a  complete  filling  for  "taps"'  either 
through  tooth  structure  or  other  filling  material,  and  as  filling 
for  "  lined  "  cavities  of  large  size  and  with  frail  walls,  so  situ- 
ated as  not  to  require  a  resistant  to  attrition,  has  been  so  satis- 
factorily demonstrated  during  the  past  twenty -five  years  as  to 
offer  every  guarantee  that  such  use  of  it  will  be  eminently 
satisfactory  alike  to  patients  and  operators. 


OXY-CHLORIDE    OF    ZINC.  151 

ARTICLE   XIV. 
OXT-CHLOEIDE   OF  ZINC. 

IT  is  now  more  than  twenty  years  since  M.  Sorel,  having  de- 
vised the  combination  of  oxide  of  zinc  and  a  solution  of 
chloride  of  zinc,  suggested  its  possible  value  for  the  "  stopping 
of  hollow  teeth."  as  its  plasticity,  when  first  mixed,  and  its  sub- 
sequent rapid  hardening  and  apparent  impenetrability  to  moist- 
ure, seemed  to  render  it  peculiarly  applicable. 

Within  a  couple  of  years  or  so  after  its  discovery,  my  friend 
Mr.  Edward  Parrish  —  afterwards  of  the  Philadelphia  College 
of  Pharmacy  —  received  from  Europe  a  sample  of  the  material 
as  prepared  for  dental  use,  and.  calling  my  attention  to  it,  gave 
it  to  me  for  the  purpose  of  experimenting  as  to  its  real  worth. 

At  first,  it  promised  to  meet  certain  requirements  which  were 
admitted  to  exist,  and  which  it  was  very  desirable  should  be 
better  fulfilled ;  but  it  was  not  long  before  the  action  upon  it  of 
the  fluids  of  the  mouth  was  recognized  as  very  different  from 
that  of  ordinary  moisture,  and,  although  several  varieties  of 
this  easily-made  compound  were  soon  offered  to  the  profession, 
they  were  received  with  evident  caution  and  with  much  dis- 
trust. 

The  time  required  to  disprove  its  claims  to  be  regarded  at 
all  favorably  as  a  permanent  filling  material  was  not  very  long, 
as.  within  a  year  after  its  introduction,  many  failures  had  oc- 
curred, and  in  some  instances  the  fillings  had  almost  entirely 
disappeared ;  in  fact,  its  proper  position  was  accorded  it  with 
remarkable  promptitude. 

Recipes  for  its  manufacture,  containing  oxide  of  zinc,  silex, 
borax,  alum,  ground  glass,  etc.,  as  components  of  the  powder, 
tlier  with  deliquesced  chloride  of  zinc,  or  metallic  zinc  dis- 
solved in  muriatic  acid,  combined  with  soluble  glass,  for  the 
fluid,  were  freely  given  at  conventions  and  published  in  the 
journals;  but  its  employment  has  alwavs  been  confined,  bv  those 
best  informed  in  regard  to  it,  first,  to  the  obtuuding  of  sensi- 
tive dentine  in  superficial  or  ordinary  cavities  of  decay,  using 
it  for  this  purpose  as  a  temporary  filling ;  second,  to  the  oc- 
casional filling  of  frail  incisors,  cuspids,  and  bicuspids,  for  as 


152  PLASTICS     AXD    PLASTIC    FILLING. 

long  a  period  as  it  would  last,  but  avowedly  with  the  intention 
of  frequent  renewal;  and,  third,  as  a  lining  for  cavities  having 
thin  walls,  and  as  a  filling  for  the  larger  portion  of  very  large 
cavities,  when  it  was  proposed  to  fill  externally  either  with 
amalgam  or  gold. 

Both  recipes  and  uses  have  remained  always  practically  the 
same ;  the  adjuncts  of  silex,  alum,  ground  and  soluble  glass, 
etc.,  have  quietly  become,  to  a  great  extent,  ignored,  but  the 
oxide  of  zinc  and  borax  powder,  and  the  solutions  of  chloride 
or  muriate  of  zinc,  are  the  same  to-day  as  when  they  were 
given  us  twenty  odd  years  ago. 

With  all  its  deficiencies,  oxy -chloride,  under  a  multitude  of 
names,  such  as  os  artificial,  osteo-dentine,  crystalline,  rock, 
agate,  acme,  and  various  other  cements,  together  with  a  numer- 
ous list  called  after  their  makers  Houghton's,  Robert's,  Smith's, 
Fletcher's,  Poulson's,  Franzelius',  etc.,  has  steadily  been  given 
in  response  to  increasing  demand,  until  the  quantity  which  is 
now  used  is  something  incredible. 

In  this  connection  it  is  truly  remarkable  that  this  compound, 
so  worthless  for  general  purposes,  so  utterly  unreliable  as  a  fill- 
ing material,  so  almost  completely  ignored  by  the  "plastic- 
filler,"  should  be  used  in  such  extraordinary  amounts.  It 
seems  as  though,  in  desperation,  those  who  have  patronizingly 
styled  gutta-percha  "an  excellent  material  for  temporary  fill- 
ings," and  have  decried  amalgam  as  an  "  abomination,  used  only 
by  incapables,  and  endured  only  by  imbeciles,"  have  been  forced 
to  content  themselves  with  this  miserable  apology  for  a  plastic 
filling.  They  have  discussed  it  periodically,  even  within  the 
past  year,  repeating  again  and  again  the  few  things  that  could 
be  said  of  it ;  they  have  spoken  of  its  "  proper  manipulation  " 
just  as  though  it  were  not  far  easier  to  work  than  either  gutta- 
percha  or  amalgam.  It  has  been  not  only  admitted  to  be  a 
good  thing  under  gold,  but  a  most  excellent  device,  "  well 
worthy  of  much  consideration ;  "  this,  however,  was  not  so  re- 
garded until  after  the  plastic-fillers  had  been  so  using  it  under 
gutta-percha  and  amalgam  for  more  than  a  dozen  years!  It 
was  finally  "accepted"  concomitant  with  a  modified  oxy-chloride 
—  so  stated  —  but  the  plastic-fillers  never  knew  of  any  such 
modification ;  and  thus,  as  the  plastic-fillers  have,  gradually, 


OXY-CHLORIDE    OF    ZINC.  158 

most  completely  ignored  oxy-chloride  of  zinc  as  a  filling  ma- 
terial, the  gold- workers  have  come  to  using  it  by  the  hundred- 
weight. 

Various  efforts  have  been  made  for  the  "  improvement "  of 
oxy-chloride ;  ground  feldspar,  pulverized  French  chalk,  oxide 
of  tin,  and  many  other  like  ingredients,  have  each  been  tried 
and  abandoned.  The  most  of  these  were  found  to  act  preju- 
dicially, and  none  of  them  produced  any  decided  improvement 
over  a  well-prepared,  properly  calcined  "  Sorel  Cement." 

Some  four  or  five  years  ago,  a  method  was  proposed  for  treat- 
ing oxy-chloride  of  zinc  fillings  by  rubbing  them  with  heated 
talc ;  points  of  French  chalk  (talc)  were  secured  in  crayon- 
holders,  and,  after  being  hea.ted  over  a  spirit-lamp,  were  used  to 
smooth,  dry,  and  harden  the  surface  of  the  fillings.  These 
were  afterwards  burnished  with  agate  burnishers,  and  a  pecu- 
liarly beautiful  effect  was  thus  produced. 

It  was  found,  upon  very  limited  trial,  that  the  whole  thing 
was  deceptive,  and  that  there  was  no  value  in  it.  The  first 
fillings  which  I  introduced  and  finished  by  this  process  — 1876 
—  began  to  show  evident  signs  of  wear  in  less  than  a  month, 
and  in  less  than  a  year  positive  proof  of  its  general  inutility 
\vas  afforded  to  such  extent  as  to  warrant  its  total  abandon- 
ment. 

It  is  unquestionably  true  that  some  of  the  .oxy-chlorides 
sire  better  than  others,  for  they  are  more  thoroughly  com- 
pounded and  more  carefully  prepared ;  but  it  nevertheless 
remains  that  the  best  of  them  is  entirely  unreliable,  and  that 
no  one  of  them  is  deserving  of  rank  as  a  filling  material. 

But  oxy-chloride  has  great  value  for  the  plastic-filler  as  a 
"  liner "  of  cavities  prior  to  filling.  It  was  early  noted  that 
the  doubts  which  were  expressed  as  to  the  possibly  deleterious 
effects  of  the  material  upon  tooth-bone  were  proving  more  and 
more  groundless.  It  was  early  noted  that  the  "  chalky  "  con- 
dition of  dentine,  which  was  confident!}'  prognosed  as  likely 
to  ensue,  did  not  appear,  but  that,  on  the  contrary,  this  struct- 
ure was  maintained  in  singular  integrity.  As  year  after  year 
passed  by,  it  was  noted,  with  increasing  interest,  that  decay  was 
never  seen  under  oxy-chlorile  of  zinc,  and  thus  it  was  that  in 
"plastic  dentistry"  it  advanced  from  the  position  of  a  mere 


154:  PLASTICS     AND    PLASTIC     FILLING. 

foundation — an  advantageous,  non-conducting,  occupant  of  space 

—  to  the  dignity  of  a  complete  "  liner,"  a  preventive  alike  of  dis- 
coloration and  decay. 

It  is  only  two  years  since  Prof.  D.  D.  Smith  read  the  paper 
which  first  openly  advocated  the  use  of  oxy-chloride  "  linings  " 
from  the  therapeutic  stand-point ;  a  matter  of  vital  importance, 
a  point  for  grave  consideration,  and  one  which  it  seems  to  me 
cannot  be  controverted. 

It  is  true  that  oxy-chloride  of  zinc  remains,  most  persist- 
ently in  some  cases,  doing  duty  as  a  filling,  where  everything 
else  seems  to  fail ;  but  these  instances  are  so  very  rare,  and  the 
indications  which  point  to  this  possibility  are  so  entirely  un- 
known, that  this  fact  alone  stamps  the  filling  as  the  most  unre- 
liable of  all,  as  it  will  probably  fail  very  soon,  but  may  possibly 
last  for  many  years. 

Oxy-chloride  of  zinc  fails  in  two  ways ;  first,  and  least  nota- 
bly, from  attrition ;  for  this  reason  it  usually  lasts  best  in  cavi- 
ties upon  articulating  faces,  where  it  sustains  the  wear  incident 
to  mastication;  and,  second,  and  most  notably,  from  solution  or 
disintegration  at  the  cervical  portion  of  the  filling.  At  this 
point,  it  fails  as  decidedly  as  does  tooth-bone  —  soft  structure 

—  at  the  cervical  margins  of  metallic  fillings,  especially  those 
made  of  gold. 

This  matter  of  respective  failure,  in  this  connection,  is  most 
interesting  and  instructive  to  the  student  of  the  "  compatibil- 
ity "  theory ;  for,  observation  shows,  that  with  gold  as  a  filling 
material,  the  cervical  margin  of  the  filling  remains  intact,  while 
the  contiguous  tooth-structure  is  markedly  decayed ;  and  that 
with  oxy-chloride  as  a  filling  material  the  cervical  portion  of 
the  tooth  remains  comparatively  intact,  while  the  filling  is  rap- 
idly disintegrated. 

To  the  plastic-filler,  whose  thoughts  are  ever  upon  tooth- 
salvation,  this  fact  alone  would  decide  the  relative  value  of  the 
two  materials  as  tooth-savers,  and  he  would  rather  renew  fill- 
ings as  often  as  required  than  permit  successive  decay  to  finally 
destroy  the  tooth ;  for,  he  reasons,  filling  material  is  obtainable 
in  any  quantity,  but  tooth-bone  is  limited  in  amount,  and  teeth 
are  limited  in  number;  and  yet  he  does  not  stop  at  this  deci- 
sion, for  experience  has  taught  him  that  other  materials  are 


OXY-CHLORIDE    OF    ZINC.  155 

infinitely  more  reliable  for  filling  at  this  point  —  materials  like 
submarine  amalgam,  tin,  or,  perhaps  best  of  all,  gutta-percha. 
And  therefore  it  is,  that  although  in  some  mouths,  where  oxy- 
chloride  has  been  proven  to  do  well,  a  plastic-filler  might  use 
it  for  an  articulating  filling,  yet  he  would  never  think  of  em- 
ploying it  for  filling  appro ximal  cavities  or  cavities  approach- 
ing near  to,  much  less  impinging  upon,  the  gum. 

From  an  experience  of  twenty  years,  I  am  taught  never  to 
use  oxy -chloride  of  zinc  as  a  fitting  material ;  that  is,  as  a  ma- 
terial for  filling,  entirely,  a  cavity  of  decay ;  or  for  filling  a 
gutta-percha  or  varnish-lined  cavity  in  such  manner  as  would 
leave  the  oxy-chloride  exposed  to  the  action  of  the  fluids  of 
the  mouth. 

But,  as  I  have  stated,  this  material  is  regarded  as  inval- 
uable for  use  as  a  "  lining '?  to  cavities  having  thin,  frail 
walls,  and  it  is  for  this  purpose,  and  for  this  only,  that  I  ever 
use  it. 

Oxy-chloride  of  Zinc,  as  prepared  for  dental  use,  consists 
of  a  powder  and  a  fluid.  Portions  of  each,  being  mixed  to- 
gether into  a  thick  creamy  paste,  soon  form  a  reasonably  hard, 
wrhitish  cement.  The  powder  is  made  by  thoroughly  rubbing- 
together,  in  a  small  mortar,  two  grains  of  borax  and  four  penny- 
weights of  oxide  of  zinc.  I  give  these  proportions  in  troy 
weight,  because  the  weights  sold  with  dentists'  scales  are 
usually  of  that  denomination.  These  are  then  placed  in  a 
small  crucible,  and  subjected  to  a  glowing  red  heat  for  from 
seven  to  ten  minutes;  in  this  way  is  formed  a  "frit,"  which, 
when  cool,  is  finely  pulverized  by  again  rubbing  it  in  the 
mortar. 

Sixteen  pennyweights  of  oxide  of  zinc  are  then  calcined  for 
three  or  four  minutes,  at  a  moderate  red-heat,  and  allowed  to 
cool.  This  calcined  oxide  is  then  gradually  <«!<l«l  to  the  pul- 
verized frit  in  the  mortar  until  all  is  thoroughly  rubbed  up 
together.  The  zinc  is  calcined  for  the  purpose  of  freeing  it 
from  the  moisture  which  it  always  absorbs  when  exposed  to 
the  air,  and  the  powder  should  be  kept  in  a  tightly-stopped 
bottle  in  order  to  maintain  this  calcined  condition.  It  is 
added  in  quantity,  to  the  frit,  which  is  sometimes  quite  yellow, 
for  the  purpose  of  securing  the  whitest  possible  oxy-chloride ; 


156  PLASTICS    AND    PLASTIC    FILLING. 

this  can  be  afterwards  shaded,  if  desired,  by  the  addition  of 
chrome-yellow. 

The  fluid  is  made  either  by  saturating  muriatic  acid  with 
metallic  zinc  —  allowing  the  solution  to  clear  and  then  decant- 
ing—  or,  by  dissolving  half  an  ounce  of  chloride  of  zinc  in 
two  or  two  and  a  half  drams  of  water;  the  latter  is  the 
easier  and,  I  think,  the  better  method.  Considerable  heat  is 
generated  by  this  dissolving,  therefore  the  bottle  in  which  it  is 
done  should  not  be  too  tightly  stopped.  After  several  shakings, 
the  contents  should  be  allowed  to  settle  for  some  days,  when 
the  perfectly  clear  portion  of  fluid  should  be  poured  off  for 
use.  If  it  does  not  clear,  filter  the  solution. 

For  the  mixing  of  oxy-chloride  of  zinc,  and,  indeed,  any  of 
the  zinc  plastics,  a  piece  of  plate-glass,  one-fourth  of  an  inch 
thick,  two  or  two  and  a  half  inches  wide,  and  three  or  three 
and  a  half  inches  long,  will  be  found  very  convenient  and  de- 
sirable. Upon  this  is  placed  one  or  more  small  portions  of 
fluid,  each  portion  separate  from  the  others,  distant  an  inch  or 
so ;  a  sufficient  quantity  of  the  powder  is  then  poured  upon 
the  slab,  and  the  materials  are  ready  for  mixing. 

It  is  usually  directed  that  the  cavity  be  filled  with  oxy-chlo- 
ride, and  that  a  sufficient  length  of  time  be  given  for  the  com- 
plete hardening  of  the  material  —  a  day  or  more  —  when,  it  is 
said,  it  should  be  burred  out  as  desired,  and  the  covering  filling 
of  gold  or  amalgam  be  made.  These  directions,  together  with 
the  teaching  that  the  main  objects  accomplished  are  the  secur- 
ing of  a  non-conducting  medium  which  largely  fills  the  cavity, 
and  thus  prevents  the  necessity  for  so  much  irritation  to  the 
surroundings  and  so  great  expenditure  of  time  in  the  introduc- 
tion and  consolidation  of  the  gold  filling,  are  not  at  all  in  con- 
sonance with  the  ideas  of  a  pjastic -filler,  for  it  is  recognized 
that  oxy-chloride  of  zinc  is  a  notable  shrinker ;  that  it  begins 
to  shrink  in  a  short  time  after  it  is  introduced,  and  that  it  con- 
tinues shrinking  for  several  days ;  that  this  shrinkage  must 
result  in  a  defective  lining,  and  it  is  therefore  taught,  from  the 
"  plastic "  stand-point,  that  the  oxy-chloride  should  be  intro- 
duced in  small  portions,  and  that  it  should  be  pelleted — see 
"  pelleting,"  in  Technicalities  —  into  position  against  the  walls 
of  the  cavity. 


OXY-CHLORIDE    OF     ZIXC.  157 

Furthermore,  it  is  not  regarded  that  the  main  objects  secured 
are  non-conduction  and  the  filling  of  the  cavity,  in  large  de- 
gree, with  a  material  which  will  prevent  undue  irritation  from 
dental  manipulation,  for  in  plastic  filling  oxy-chloride  is  never 
used  for  its  non-conducting  characteristic,  and  is  never  needed  in 
lulk,  but  is  rather  desired  in  its  thinnest  possibility,  as  obviating 
shrinkage,  and  none  of  the  materials  used  in  filling,  necessitate 
any  dental  irritation. 

In  plastic  dentistry,  the  main  objects  which  are  regarded  as 
secured  by  the  "  lining  "  with  oxy-chloride.  are,  first,  exemption 
from  further  decay ;  second,  maintenance  of  color,  improvement 
of  color  in  discolored  teeth,  and  prevention  of  tooth  discolor- 
ation from  filling  materials  liable  to  produce  such  result ;  third, 
the  securing  of  solid  support  for  amalgam,  when  gutta-percha  — 
a  yielding  material  —  is  used  as  a  non-conducting  pulp  protector 
or  guard  for  cervical  edge  of  cavity  ;  and,  fourth  —  incidentally 
—  as  a  strengthener  to  frail  walls  which  would  be  liable  to 
fracture  during  the  progress  of  "treating"  a  tooth. 

Oxy-chloride  of  zinc,  though  used  with  impunity  in  pulpless 
teeth, —  pulp  cavities  filled  with  gutta-percha, —  should  be  used 
with  much  caution  in  teeth  of  soft  structure  and  non-recuper- 
ative attributes,  containing  living  pulps.  Its  introduction  into 
cavities  in  such  teeth  should  always  be  preceded  by  arnica 
plaster;  adhesive  plaster;  gutta-percha,  —  "low  heat,"-— or 
oxy-sulphate  of  zinc,  as,  by  these  means,  pulp  irritation,  from 
the  chloride  of  zinc  fluid,  is  prudently  guarded  against. 

Oxy-chloride  of  zinc  is  best  mixed  by  approaching  a  portion 
of  powder  to  the  drop  of  fluid,  and  pushing  it  into  it  by  the 
point  of  the  spatula.  It  is  taken  up,  so  to  speak,  by  the  liquid, 
and  in  this  way  an  approximate  to  the  required  proportions  of 
fluid  and  powder  is  obtained,  when  the  addition  of  a  very  small 
quantity  of  powder  will  make,  by  the  usual  spatula  mode  of 
mixing,  a  cream}'  mass  of  thick  viscidity,  which,  taken  upon 
the  end  of  the  spatula,  should  be  placed  in  position  in  the  cav- 
ity and  pressed  gently  against  the  wall. 

Having  pellets  of  cotton  wool  in  readiness,  these  should  be 
taken  and  used  as  described  in  "  pelleting."  In  a  few  minutes — 
five  or  ten  —  the  lining  will  be  sufficiently  "  set"  to  proceed  with 
the  covering  filling. 


158  PLASTICS    AND    PLASTIC    FILLING. 

The  experience  which  I  have  had  in  the  direction  of  "lining" 
teeth  with  oxy-chloride,  makes  it  seem  to  me  strange  to  hear 
the  therapeutic  action  of  filling  material  denied,  and  still  more 
strange  to  see  the  constant  presentation  of  certain  qualities  as 
"resistance  to  the  fluids  of  the  mouth,"  "  resistance  to  attrition," 
etc.,  as  characteristics  of  a  material  which  are  essential  to  the 
saving  of  teeth.  The  idea  is  ever  tacitly  accepted,  that  a  can'/// 
of  decay  must  be  filled  with  ONE  MATERIAL  ichich  shall  combine 
all  the  varied  attributes  needed  for  success,  totally  ignoring  the 
palpably  presented  fact,  that  materials  which  possess  certain  tooth- 
saving  attributes,  and  are  deficient  in  others,  can  be  utilized  IX 
THEIR  PROPER  PLACES,  while  these,  again,  can  be  protected  //// 
other  materials,  which,  though  deficient  in  essentials  possessed  by 
the  former,  are,  in  wonderful  degree,  possessed  of  the  very  essen- 
tials which,  in  these,  have  been  found  wanting. 

I  have  hundreds  of  cavities,  in  the  teeth  of  my  patients, 
from  which  gold  fillings,  introduced  by  some  of  the  very  best 
operators  of  our  country,  failed  from  surrounding  decay,  and 
literally  dropped  out,  in  from  two  to  five  years,  and  in  which 
amalgam  fillings  had  been  tried,  some  of  them  by  the  same 
operators,  with  but  little  better  success,  in  which  "  linings  "  of 
oxy-chloride,  protected  by  amalgam  coverings,  have  done  good 
service  for  from  six  to  twelve  years,  and  are  yet  in  such  con- 
dition as  bids  fair  to  afford  years  of  service  during  the  future. 

I  cannot  dismiss  the  subject  in  hand  without  referring  spe- 
cially to  oxy-chloride  as  a  restorer  of  color  to  discolored  teeth. 
It  has  been  my  experience  that  discolored  teeth  in  which 
"  bleachers "  have  been  used,  gradually  lose  the  renewal  of 
beauty  which  had  been  afforded  them,  and  that  the  after  dis- 
coloration is  often  worse  than  the  first.  For  this  reason  I  have 
long  abandoned  this  method  of  "  whitening  "  teeth,  only  resort* 
ing  to  it  for  an  occasional  experiment,  as  various  materials 
or  combinations  have  been  successively  recommended.  Of  all 
these,  I  have  never  yet  tried  any  one  which  has  proved  so 
satisfactory,  and  has  maintained  so  generally  a  permanent  ef 
feet,  as  oxy-chloride  of  zinc. 

Quite  early  in  its  use,  the  capability  which  it  possesses  of 
producing  a  marked  whitening  of  teeth  was  duly  noted.  In 
many  cases  of  exc  edingly  frail  front  teeth,  with  very  thin 


OX  Y -CHLORIDE    OF     ZINC.  159 

labial  enamel,  its  introduction  caused  such  "  spottings "  of 
white  through  this  transparent  tissue  as  to  render  it  necessary, 
for  beauty,  that  the  filling  should  be  removed  and  replaced  by 
an  oxy-chloride  which  had  been  shaded  by  chrome-yellow  ex- 
pressly for  this  purpose. 

It  was  an  easy  deduction  that  thus  indicated  the  worth  of  a 
white  oxy-chloride  as  an  adjunct  to  the  old-fashioned  prepared 
chalk  and  the  scraped  French  chalk  —  talc  —  which  have  been 
used  for  half  a  century  to  remove  the  heavy  discoloration 
prior  to  "  bleaching,"  and  which,  with  me,  have  still  retained 
their  value ;  therefore,  I  would  now  recommend,  as  the  result 
of  fifteen  years'  experience,  that  the  whitening  of  teeth  —  I 
discard  the  term  "  bleaching "  as  inappropriate  —  should  be 
accomplished  by  first  entering  thoroughly  and  removing,  as 
much  as  possible,  consistent  with  maintenance  of  strength  of 
tooth,  all  discolored  dentine,  especially  at  the  cervical  portion ; 
then,  after  proper  treating,  the  canal  should  be  filled  for  three- 
fourths  its  length  from  the  apical  foramen.  If  this  is  done 
with  cotton,  it  should  be  perfectly  protected  by  gutta-percha 
covering. 

The  cavity  should  now  be  packed  with  prepared  chalk  or 
pulverized  —  scraped  —  French  chalk,  and  this  should  be  cov- 
ered either  with  small  pellets  of  cotton,  tightly  packed,  dry, 
and  afterwards  moistened  with  varnish  of  gum-sandarac,  or 
with  an  oxy-chloride  or  zinc-phosphate  capping.  The  chalks 
act  to  remove  the  organic  discoloration  just  as  they  do  in  the 
usual  household  application  of  these  materials  for  removal  of 
such  stains  from  dress  goods,  floors,  carpets,  etc. ;  and,  indeed, 
I  was  told,  more  than  thirty  years  ago,  that  it  was  the  domes- 
tic use  of  chalks  for  this  purpose  that  first  suggested  their  like 
employment  in  dentistry. 

A  few  days  should  be  given  for  the  action  of  the  chalk,  when 
it  should  be  removed,  and,  if  indicated,  a  second  application 
should  be  made.  When  the  color  has  been  approximately 
restored,  the  tooth  should  be  placed  under  rubber,  and  the 
cervical  portion  "  lined "  with  a  thin  film  of  very  ichite  oxy- 
chloride.  The  object  of  this  thin  lining  is,  that  very  little,  if 
any,  pain  is  induced  by  the  attenuated  oxy-chloride,  while  the 
pain  which  is  apt  to  result  from  a  bulk  of  this  material  —  even 


160  PLASTICS    AND    PLASTIC    PIL.LIXG. 

in  pulpless  teeth  —  is  sometimes  very  considerable,  and  may  be 
of  some  length  of  duration. 

After  this  lining  has  "  set,"  a  process  usually  requiring  fifteen 
or  twenty  minutes,  I  prefer  to  fill  the  cervical  portion,  as  far 
down  as  the  edge  of  the  lining,  with  gutta-percha,  as  this  ma- 
terial is  easier  of  removal,  if,  at  any  future  period,  it  is  deemed 
desirable  to  relieve  peridental  irritation  by  entering  the  canal. 

The  crown  portion  should  next  be  lined  with  oxy-chloride, 
so  shaded  as  to  result,  if  possible,  in  a  color  lighter  than  that 
of  the  adjoining  teeth.  The  reason  for  this  effort  is  that  the 
moisture  will  detract  somewhat  from  the  color  attained,  and  the 
final  result  will  thus  be  exactly  that  which  is  desired. 

Oxy-chloride  is  usually  shaded  with  chrome-yellow,  and,  very 
rarely,  with  lamp-black. 

The  tooth  may  now  be  filled  with  an  amalgam  made  from 
one  part  of  "  contour  "  and  two  parts  of  "  facing  "  alloy,  if  a  re- 
sistant filling  is  required  ;  or  it  may  be  filled  with  gutta-percha, 
if  the  filling  is  not  exposed  to  attrition,  or  if  the  tooth  has  been 
intermittingly  troublesome  and  may  possibly  require  an  occa- 
sional relief  dressing. 


AETICLE   XV. 
OXT-SULPHATE  OF  ZINC. 

plastic  preparation  is,  even  more  than  the  oxy-chloride 
-*-  of  zinc,  to  be  regarded  as  not  at  all  useful  as  a  filling  ma- 
terial, but,  like  the  oxy-chloride,  it  is  a  most  valuable  adjunct 
in  its  proper  place.  This  also  consists  of  a  powder  and  a  fluid. 
The  powder  is  composed  of  calcined  sulphate  of  zinc,  one  part, 
and  calcined  oxide  of  zinc  two,  and  sometimes  three  parts. 

The  sulphate  of  zinc  is  first  thoroughly  calcined,  at  a  glowing 
red  heat,  and,  when  cool,  is  reduced  to  a  fine  powder  by  hard 
rubbing  in  a  mortar.  The  oxide  of  zinc  is  then  calcined  as  if 
for  oxy-chloride  powder,  and,  when  cool,  is  added  to  the  finely 
powdered  sulphate.  The  powder  should  be  kept  in  a  tightly 
stoppered  bottle. 

The  fluid  is  made  by  dissolving  fifteen  grains  of  gum-arabic 
in  a  half  ounce  of  pure  water,  and,  when  completely  dissolved, 


OXY-SULPHATE    OF    ZINC.  161 

adding  one  grain  of  sulphite  of  lirne.     Filter  solution  through 
absorbent  cotton. 

Oxy- sulphate  of  zinc  is  probably  one  of  the  best  pulp  pro- 
tectors and  pulp  cappers  which  has  ever  been  used ;  it  is  easy 
of  adaptation,  quite  as  much  so  as  gutta-percha,  arnica  plaster, 
adhesive  plaster,  or  the  oxide  of  zinc  and  oil  of  cloves  pad;  but 
it  possesses  certain  peculiarities  which  are  very  valuable,  and 
which  appertain  to  no  other  capper  or  protector,  except,  per 
haps,  plaster  of  Paris,  which  it  very  much  exceeds  in  rapidity 
of  setting  and  in  density  after  it  has  become  hard.  Together  with 
these  attributes,  it  is  not  only  perfectly  non-irritating  alike  to 
sensitive  dentine  and  to  the  dental  pulp,  but,  from  its  admixed 
sulphate  of  zinc,  is  accredited,  with  much  show  of  reason  from 
extended  experimentation,  with  therapeutic  value  as  an  astrin- 
gent, antiphlogistic  pulp  preserver. 

This  is  mixed  upon  the  glass  slab  already  described,  much 
in  the  same  manner  as  is  oxy-chloride,  but  it  should  be  mixed 
much  thinner ;  indeed,  it  should  be  but  little  more  than  milky 
in  its  consistency,  and  certainly  not  thicker  than  very  ordinary 
cream. 

It  should  then  be  worked  with  the  spatula  until  it  begins 
to  give  the  least  perceptible  evidence  of  thickening,  when  it 
should  be  taken  upon  the  end  of  the  spatula  and  placed 
accurately  in  position  in  the  cavity  by  being  pushed  off  the 
spatula  by  a  moderately  fine  probe. 

It  will  adhere  nicely  to  the  dentine  if  it  is  properly  manipu- 
lated, and,  in  its  still  yieldingly  plastic  condition,  can  be  spread, 
as  required,  by  careful  working  with  the  tiny  end  of  the  probe. 
It  should  not  be  worked  after  it  ceases  to  flow,  comparatively 
easily,  under  this  instrumentation. 

Another  method,  and  a  very  excellent  one,  particularly 
adapted  to  difficult  and  inaccessible  capping,  is  that  of  pre- 
paring a  pellet  of  cotton,  no  larger  than  the  head  of  a  small 
pin,  which  should  be  dipped  in  the  milky  zinc-sulphate  imme- 
diately after  it  is  mixed.  The  tiny  capping  is  then  gently 
placed  accurately  in  position,  and  will  be  readily  secured  in 
place  by  touch-ing  its  edges  with  a  small,  smooth-ended  instru- 
ment. 

It  now  requires  a  few  minutes  —  from  five  to  fifteen  —  to  set 
11 


162  PLASTICS    AND    PLASTIC    FILLING. 

sufficiently  for  progressive  work,  and  then  permits  the  intro- 
duction of  oxy-chloride  side  linings,  or  of  amalgam  or  gutta- 
percha  fillings. 

This  operation  is  one  requiring  considerable  dexterity,  and 
some  practice,  for  its  acceptable  accomplishment;  but  with 
these  it  becomes  a  neat  and  most  reliable  method  for  pro- 
tecting almost  exposed  and  exposed  pulps. 


AETICLE   XVI. 
ZINC-PHOSPHA  TE. 

THE  attempted  utilization  of  the  acids  of  phosphorus  for 
the  purpose  of  compounding  filling  materials  is  now  of  quite 
respectable  antiquity  when  compared  with  the  still  moderate 
age  of  dentistry  as  a  profession ;  for  the  old  recipe  of  Oster- 
mann,  published  in  1832,  may  almost  be  regarded  as  cotempo- 
rary  with  the  "  silver  paste  "  of  M.  Taveau. 

This  formula,  for  which  I  am  indebted  to  Dr.  De  Montreville, 
is  as  follows : 

"  Take  13  parts  of  finely  powdered  lime  and  12  parts  of 
anhydrous  phosphoric  acid.  This  compound  is  moist  during 
the  mixing,  and  while  in  that  condition  is  to  be  put  into  the 
cavity  of  the  tooth,  the  cavity  being  prepared  in  the  usual 
manner.  The  filling  must  be  used  in  one  or  two  minutes 
after  it  is  made,  as  it  almost  instantly  hardens.  The  lime 
must  be  caustic  lime,  and  chemically  pure."  A  second  old 
formula,  furnished  me  by  the  same  gentleman,  reads  thus : 

"  Mix  equal  parts  of  finely-powdered  silicate  or  fluate  of 
lime  and  alumina,  with  a  sufficient  quantity  of  water  to  make 
a  homogeneous  paste.  This  is  to  be  introduced  into  the  cavity 
of  the  tooth  to  be  filled,  and  the  drying  of  the  mass  is  to  be 
aided  by  warming  it  with  heated  instruments." 

From  these  two  initial  cements  the  phosphoric  filling  ma- 
terials of  the  present  day  seem  to  have  gradually  developed, 
but  it  is  only  during  the  past  few  years  that  the  attention  of  the 
profession  has  been  especially  directed  to  them.  The  cements 
of  Rostaigne,  Poulson,  Grass  and  "Worff,  Fletcher,  and  others  — 


ZINC-PHOSPHATE.  163 

a  series  of  variably  good  materials  —  were  quickly  followed  by 
many,  more  or  less  worthy,  imitations  of  the  genuine  article. 
All  the  former  are  entitled  to  tlie  appellation  of  "  ZINC-PHOS- 
PHATES," for  they  have  the  obdurate  nitrate  of  zinc  as  their 
powder,  which  is  made  into  paste  with  variously,  and  in  some 
instances  accurately  and  scientifically,  prepared  fluid  or  crystals 
of  such  form  of  phosphoric  acid  as  makes  reasonably  durable, 
and  sometimes  remarkably  durable  fillings ;  while  many  of  the 
latter  are  merely  OXY-PHOSPHATES  OF  ZINC, — for  their  powder 
is  nothing  but  calcined  oxide  of  zinc, —  a  material  incapable,  so 
far  as  is  known,  of  making  a  resistant  cement ;  or  yet  worse,  a 
mixture  of  oxide  of  zinc  and  oxide  of  tin ;  while  the  fluid  is 
merely  glacial  phosphoric  acid  dissolved  in  water  and  either 
evaporated  to  the  "  desired "  (?)  consistence  or  permitted  to 
form  a  natural  separation,  by  time,  and  then  decanted. 

The  former  of  these  methods  is  eminently  unscientific,  as  ex- 
periment proves  it  to  be  impossible  ever  to  repeat  the  process 
with  a  known  result ;  and  eminently  unsatisfactory,  as  none  of 
the  results  make  a  cement  which  responds  to  a  single  "  test " 
for  a  good  "  zinc-phosphate." 

By  the  latter  method,  with  the  nitrate  of  zinc  powder,  an 
approximate  to  a  good  result  is  produced,  but  with  the  calcined 
oxide  of  zinc  only  a  poor  cement,  at  best,  is. made. 

The  amount  of  work  which  has  been  done  in  the  direction 
of  these  cements  is  something  extraordinary ;  and  it  is  equally 
noteworthy  that  only  those  whose  "  contributions  to  knowl- 
edge," in  this  line  of  experiment,  have  proven  that  they  knew 
nothing  about  it,  have  ventured  to  place  themselves  upon  the 
record  ! 

There  is  no  other  plastic  filling  material  in  regard  to  which 
I  have  had  such  hesitancy  in  both  speaking  and  writing,  even 
in  the  familiar  way  of  correspondence,  and  no  direction  in  which 
I  am  better  satisfied  to  be  regarded  as  "  not  posted,"  for  I  feel 
sure  that,  so  far,  those  who  know  most  of  it,  recognize  that 
they  know  but  little,  while,  unfortunately  for  the  society  records, 
and  for  the  members  of  the  profession  who  depend  upon  them 
for  information,  those  who  know  nothing  of  it,  have  freely 
given  all  they  know. 

I  have  been  for  years  in  constant  correspondence  with  those 


164  PLASTICS    AND    PLASTIC    FILLING. 

whom  I  had  reason  to  suppose  most  earnest  and  best  informed 
in  this  work,  and  time  and  again  have  we  thought  that  "  suc- 
cess "  was  to  reward  our  efforts ;  but  the  ruthless  evidence  of 
deteriorating  fluid,  and  crystals,  and  disintegrating  fillings  has 
repeatedly  dampened  our  ardor  until  it  has  wellnigh,  at  times, 
extinguished  our  zeal. 

But  ever  before  us  have  been  the  provings  of  the  possibility  ; 
many  of  us  have  seen  the  fillings  of  good  "  zinc-phosphate  " 
which  have  done  two,  three,  four,  and  more  years  of  service, 
and  are  yet,  practically,  as  good  as  when  they  were  made.  I 
have  fillings  in  the  mouths  of  patients,  upon  the  articulating 
faces  of  which  I  punctured  little  indentations,  that  after  two 
years  of  service  remain  just  as  they  were  at  first.  I  have 
fillings  in  mouths  in  which  beautiful  gold-work  failed  largely, 
in  from  one  to  two  years,  and  in  which  zinc-chloride  lasts  but  a 
few  months,  that  now,  after  more  than  two  years  of  trial,  are 
about  as  good  as  when  introduced. 

These  results  are  mostly  from  Poulson's  rock-crystal  zinc- 
phosphate-— a  material  which  has  not  been  produced  of  late, 
but  towards  the  reproduction  of  which  strenuous  and  promis- 
ing efforts  are  being  made. 

It  is  from  the  behavior  of  this  material,  which  has  been 
tried  and  found  worthy,  that  I  collate  the  "tests"  for  a  "good" 
zinc- phosphate,  and  my  experience  indicates  that  just  m  pro- 
portion as  any  of  these  preparations  respond  approximately  to 
the  tests  given,  so  will  fillings  made  from  them  average  durable 
and  satisfactory. 

Like  the  other  zinc  plastics,  the  zinc-phosphates  are  prepared 
for  use  in  the  form  of  a  pbwder  and  fluid  or  crystals. 

The  powder  is  made  by  treating  oxide  of  zinc  with  nitric 
acid,  evaporating  to  dryness,  calcining,  and  pulverizing. 

This  work,  so  far  from  being  an  affair  of  two  or  three  hours, 
is  a  matter  of  several  days  and  nights,  consecutively,  for  the 
production  of  even  a  moderate  amount. 

The  powder  thus  prepared  is  readily  distinguishable  from 
the  worthless  oxide  of  zinc  powders  by  its  dry,  quick  fineness ; 
&  peculiar  cracking  apart  of  the  bulk  of  powder  as  the  bottle 
containing  it  is  slowly  revolved;  by  its  feeling  "of  slight  grit, 


ZINC-PHOSPHATE.  165 

be  it  never  so  fine,  and  by  its  decided  weight  as  compared  with 
any  oxide  of  zinc  powder. 

This  powder,  with  a  good  fluid  or  crystal  phosphoric  acid,  is 
capable  of  making  a  very  resistant  cement. 

So  far  as  I  am  aware,  all  the  acid  menstrua  are  fluid  when 
first  made ;  but,  after  being  prepared,  the  changes  which  super- 
vene are  peculiar  in  character  and  very  numerous.  In  most 
cases,  the  limpid  fluid  or  syrup  retains  its  clearness  only  a  few 
days  or  weeks,  when,  gradually,  a  cloudy  appearance  is  observ- 
able ;  this  increases  until  a  thick,  whitish  paste  results ;  this 
again  separates  into  sediment  and  supernatent  limpid  fluid. 

It  has  been  stated  that  such  preparations  make  "equally 
good  "  cements  during  any  and  all  of  these  phases ;  but  experi- 
ence proves  that  it  would  be  more  correct  to  regard  them  as 
all  equally  bad,  for  no  cement  made  from  any  such  fluid  or 
paste  does  any  credit  to  "  zinc-phosphate." 

In  some  fluids  the  limpid  fluidity  changes  to  turbidity,  and, 
without  passing  through  the  paste  form,  gradually  separates 
into  sediment  and  clear  fluid.  This  fluid  "  keeps  "  indefinitely, 
and,  with  a  proper  powder,  makes  a  cement  which  may  appro- 
priately be  styled  a  "  bastard  "  zinc-phosphate.  It  has  a  family 
likeness  to  the  genuine  article,  but  its  working,  and  its  com- 
paratively prompt  disintegration  in  the  mouth,  proves  its  ille- 
gitimacy. 

Occasionally  a  clear  fluid  is  made  which,  for  a  time,  is  as 
good  as  fluid  can  be.  It  maintains  its  integrity  surprisingly  ; 
it  works  quick  and  well ;  it  makes  a  reasonably  good  cement ; 
but  it  gradually,  and  without  apparent  change,  except  to  an 
expert,  deteriorates.  This  change  is  merely  one  from  quick, 
fluidity  to  slight  viscidity.  It  is  scarcely  perceptible  except  to 
a  practised  eye,  but  is  readily  noted  by  almost  any  one  when 
attention  is  directed  to  it.  When  this  change  takes  place,  the 
working  of  the  cement  also  changes  entirely.  It  works  easier ; 
sets  much  more  slowly  ;  becomes,  generally,  much  more  accepta- 
ble, and  of  such  material  thousands  of  unreliable  fillings  have 
already  been  introduced. 

Up  to  the  present  time  it  has  not  been  PROVEN  that  any  fluid 
makes  as  good  cement  as  does  crystal  acid.  But  here,  again,  is 
much  circumspection  necessary  ;  for  it  seems  to  be  essential  to 


166  PLASTICS    AND     PLASTIC    FILLING. 

"  excellent  "  results  that  the  syrupy  acid  should  change  to  hard, 
rock-like  crystals,  and  not  to  feathery,  flaky,  waxy  crystals. 

When  rock-like  crystals  are  obtained,  they  are  to  be  melted 
in  very  small  quantity,  and  with  very  great  care,  to  prevent 
ebullition,  over  the  flame  of  a  spirit-lamp.  It  has  been  directed 
to  use  a  spoon  of  platinum  for  this  purpose ;  but  this  is  not 
requisite,  as  any  ordinary  teaspoon  is  appropriate. 

When  melted,  the  crystals  assume  a  clear,  sticky  viscidity. 
This  syrup  is  then  to  be  scraped  from  the  tip  of  the  spoon- 
bowl  —  where  it  is  best  that  it  be  placed  for  melting  —  on  to 
the  glass-mixing  slab.  The  powder  should  now  be  poured  out, 
as  thus  a  moment  is  given  the  syrup  for  cooling.  If  mixed 
while  the  syrup  is  hot,  the  zinc-phosphate  sets  almost  instantly, 
indeed,  so  rapidly  is  this  change  sometimes  effected,  and  with 
such  evolution  of  heat,  that  it  is  dangerous  to  take  the  mass  in 
the  fingers  lest  one  be  burned. 

It  must  be  understood  that  the  illustrations  given  of  changes 
and  peculiarities  of  fluid  and  semi-solid  menstrua  are  merely 
a  typal  few  of  the  many  which  have  been  recognized,  and  which 
are  constantly  being  added  to,  and  that  it  would  be  wholly  un- 
profitable to  continue  citations  of  them,  as  practitioners  cannot, 
by  this  means,  be  made  judges  of  the  comparative  value  of  the 
various  zinc-phosphate  and  oxy-phosphate  preparations. 

It  is  only  by  "  working-tests  "  that  this  can  be  decided,  and  it 
is  for  this  reason  that  I  shall  direct  particular  attention  to  them. 
My  facilities  for  noting  these  have  been  very  extensive,  for  I 
have  been  in  receipt  of  all  the  preparations  made,  both  in 
Europe  and  our  own  country,  for  nearly  three  years ;  of  these 
I  had  introduced,  more  than  a  year  since,  over  five  hundred  ex- 
perimental fillings,  all  tabulated,  and  all  under  frequent  inspec- 
tion, and  from  this  observation  I  have  obtained  such  data  as  I 
have  reason  to  believe  will  give  zinc-phosphate — at  least,  as 
low  made  —  its  proper  value. 

It  has  been  intimated  that  the  zinc-plastics  seem  destined  to 
supersede  amalgam ;  bat  I  regard  such  opinion  as  without  the 
slightest  foundation,  and  based  alike  upon  ignorance  of  the 
progress  which  has  been  made  in  amalgams,  and  of  the  defi- 
ciencies which  notably  characterize  the  oxy-chlorides,  the  <>xy- 
phosphates,  and  even  the  best  of  the  zinc-phosphates. 


ZINC-PHOSPHATE.  167 

It  is  true  that  the  zinc-plastics  have  a  better  color  than  amal- 
gam, but  in  no  other  respect  do  they  compare  favorably  with 
it  as  filling  materials. 

When  a  zinc-phosphate  is  really  "good,"  it  is  very  good; 
and,  although  it  is  much  more  difficult  to  work  than  any  other 
plastic  filling  material,  yet  the  practice  which  has,  necessarily, 
to  be  given  to  overcome  this,  is  by  no  means  unworthily  be- 
stowed, for  the  durability  of  a  good  zinc-phosphate  filling  is  at 
least  from  three  to  five  times  that  of  the  average  oxy-chloride 
of  zinc  filling,  and  its  density  makes  it  of  great  value  even  on 
the  articulating  faces  of  teeth.  On  the  contrary,  poor  zinc- 
phosphates,  and  even  the  best  oxy-phosphates,  are,  comparatively, 
worthless  materials.  They  are  better  than  the  average  oxy- 
chlorides,  but  compared  with  good  zinc-phosphates  they  are 
quite  inferior.  They  are,  moreover,  very  alluring  and  equally 
deceptive ;  for  they  mix  nicely,  work  easily,  set  slowly,  and 
ajijuiri'iitly  make  very  nice  fillings;  but  it  requires  only  a  few 
months — six  to  twelve  —  to  demonstrate  that,  although  they 
promise  much,  they  perform  but  little. 

I  wrote  of  them,  more  than  a  year  since,  that  they  made  "a 
thick,  tough,  doughy  mass ;  they  are  easily  and  handsomely  in- 
troduced into  cavities;  they  set  slowly,  and  thus  give  time  for 
careful  manipulation ;  they  finish  nicely,  and  they  make  miser- 
able, good-for-nothing  fillings  I n  and  the  opinion  then  offered 
has  been  most  fully  corroborated  by  the  results  which  have 
since  been  noted. 

MIXING  ZINC-PHOSPHATE. 

In  mixing  zinc-phosphate  for  " testing"  a  portion  of  fluid 
equal  to  one  or  two  drops,  or  ten  grains  of  crystals,  melted, 
should  be  placed  upon  a  glass  slab,  and  more  than  sufficient 
powder  should  be  poured  out  near  to  it.  A  bulk  of  powder 
alo>if  c^iKil  in  size  to  the  bulk  of  fluid  should  then  be  mixed 
with  the  fluid  by  means  of  a  suitably  shaped  steel  spatula. 
This  should  make  a  mixture  of  a  thick,  creamy  consistence. 

Then  a  little  more  powder  should  be  added  and  quickly  and 
forcibly  made  into  mass  by  thorough  spatulation. 

It  is  possible  that  yet  a  little  more  powder  may  be  required 
to  gfive  the  mass  the  desired  consistence  for  strength  and  dura- 


168  PLASTICS    AND     PLASTIC    FILLING. 

bility,  but  it  is  better  that  the  "  mix  "  be  a  proper  one  by  the 
two  additions  of  powder.  The  reason  for  this  is,  that  zinc- 
phosphate  is  a  quick-setting  hydraulic  cement,  and  the  chem- 
ical combination  is  one  that  commences  promptly,  and  should 
be  the  least  possibly  interfered  with  during  its  progress  by  the 
successive  introduction  of  ingredients. 

The  mass  should  be  of  a  putty -like  consistence,  though  some 
varieties  are  directed  to  be  made  "stiff."  In  "testing,"  these 
should  be  made  according  to  directions,  so  as  to  give  them  the 
benefit  of  every  possibility. 

The  mass  should  then  be  scraped  up  on  the  spatula  and  taken 
from  it  by  the  thumb  and  forefinger. 

The  first  test  for  a  "good"  zinc- phosphate  is,  that  it  requires 
decided  force  to  take  it  from  the  spatula. 

The  mass  should  then  be  kneaded — NOT  ROLLED  —  by  two 
or  three  gentle  motions  of  the  thumbs  and  forefingers.  The 
warmth  of  these  makes  the  mass  slightly  more  plastic,  and  the 
kneading  is  of  great  value  in  producing  homogeneity. 

The  fingers  should  be  scrupulously  clean,  or  the  material  will 
be  soiled. 

The  mass  should  then  be  upon  the  end  of  the  forefinger  of 
the  left  hand,  from  which  it  should  be  removed  by  the  spatula 
and  placed  on  the  palm  of  the  same  hand,  and  then  gently 
rolled  into  a  round,  pill -like  pellet. 

NOTE. —  Up  to  this  point  the  directions  for  preparing  zinc-phosphate  for  "  fill- 
ing" are  the  same  as  for  "testing."  At  this  point  the  pellet  should  be  made 
oval  or  elongated  for  "filling/'  but  should  be  as  spheroidal  as  possible  for  "test- 
ing," the  object  being  to  attain  a  shape  which  will  give  the  most  accurate  rebound. 

The  second  test  is,  that  it  roll  into  pellet  with  prompt  cessa- 
tion of  adhesion  to  the  rolling  finger,  and  that  it  does  not  adhere 
to  the  finger  when  it  is  pressed  upon  it  to  determine  this. 

Third  test. —  In  one  or  two  minutes,  by  the  watch,  it  should 
glaze  and  rebound  when  dropped  upon  wood,  glass,  porcelain, 
or  marble,  but  not  necessarily  upon  metal. 

fourth  test. —  In  five  minutes,  it  should  give  a  porcelain-like 
feel  and  sound  when  tapped  gently  on  the  edges  of  the  lower 
teeth,  and  should  have  no  "  sticky  "  feeling  when  pressed  be- 
tween the  finders. 


ZINC-PHOSPHATE.  169 

Fifth  test. —  In  ten  or  fifteen  minutes  it  should  be  resistant 
when  taken  between  the  teeth  and  bitten  upon ;  and,  if  bitten 
with  sufficient  force,  it  should  break  with  a  clean,  sharp  frac- 
ture. 

Sixth  test. —  In  twenty  minutes  it  should  be  difficult  of  punc- 
ture to  the  point  of  the  spatula,  even  with  considerable  force ; 
and  it  should  take  a  fine  and  persistent  burnish. 

Seventh  test. —  In  thirty  minutes  it  should  have  no  taste,  or 
at  most  an  astringent,  metallic  taste,  like  that  of  chloride  of 
zinc,  but  not  acid. 

It  should  now  be  impenetrable  to  the  point  of  the  spatula, 
even  with  decided  force,  and  should  rebound,  with  ivory-like 
'elasticity,  when  dropped  from  no  greater  height  than  an  inch. 

I  will  repeat,  that  an  experience  of  three  years  decides  me 
in  the  opinion  that  just  in  proportion  as  a  zinc -phosphate  ce- 
ment responds  approximately  or  accurately  to  these  tests,  so 
does  it  make,  in  a  majority  of  cases,  the  most  durable  and  the 
most  satisfactory  fillings  possible  to  this  filling  material. 

If  an  oxy-phosphate  or  zinc-phosphate  is  "  poor  "  or  "  doubt- 
ful," it  will  respond  to  "  testing  "  as  follows : 

First. —  It  will  not  require  so  much  force,  even  when  mixed 
"  stiff,"  to  take  the  mix  from  the  spatula. 

Second. —  It  will  adhere  to  the  finger  while  rolling  into  pellet, 
and  will  be  lifted  from  the  palm  of  the  hand  by  pressing  the 
finger  lightly  upon  it. 

Third. —  In  from  one  to  two  minutes  it  will  not  glaze  even 
though  it  rebound;  and  it  will,  usually,  not  rebound,  but  will 
fall  "  dead  "  or  motionless. 

Fourth. —  \ufive  minutes  it  may  give  porcelain-like  feel  and 
sound  when  tapped  gently  upon  the  edges  of  the  lower  teeth, 
but  will  usually  have  a  "sticky"  feeling  if  taken  and  pressed 
between  the  fingers. 

Fifth. —  In  ten  or  fifteen  minutes  it  will  not  be  resistant  be- 
tween the  teeth  ;  but  if  bitten  upon  with  gentle,  sufficient  force, 
will  admit  of  indentation. 

Sixth. —  In  twenty  minutes  it  will  permit  of  puncture  by  the 
point  of  the  spatula,  even  with  moderate  force ;  and  it  will  not 
take  a  persistent  burnish,  even  though  it  admit  of  temporary 
polish  from  the  burnisher. 


170  PLASTICS    AND     PLASTIC    FILLING. 

Seventh. —  In  thirty  minutes  it  will  still  have  decided  taste, — 
metallic,  astringent, —  and  sometimes  even  more  than  this,  de- 
cidedly acid.  It  will,  even  yet,  permit  of  penetration  by  the 
point  of  the  spatula,  and  will  cut  like  plaster  of  Paris,  or,  even 
worse,  like  wax. 

One  of  the  most  marked  tests  of  zinc-phosphate  is  the  prompt 
loss  of  taste  on  the  part  of  a  good  material  —  in  an  hour  or 
less  —  and  the  persistence  with  which  an  inferior  material  will 
retain  the  astringent,  and  even  the  acid  taste,  sometimes  for 
days. 

This  is  attributable  to  the  imperfect  combination  of  the 
menstruum  and  powder,  which  results  in  a  mixture  of  phos- 
phoric acid  and  oxide  or  nitrate  of  zinc  —  with  acid  reaction  — 
instead  of  forming  the  neutral  hydraulic  cement  recognized  by 
plastic  dentistry  as  "  ZINC-PHOSPHATE." 

DIRECTIONS  FOR  USING  ZINC -PHOSPHATE. 

It  has  been  noted  that  the  "  mixing  "  of  zinc-phosphate  is  the 
same  for  "testing"  as  it  is  for  use  as  a  filling  material,  up  to 
the  point  when  the  mass  is  rolled  into  pellet  on  the  palm  of 
the  hand.  For  filling,  this  pellet  should  be  made  oval  or  elon- 
gated, to  further  its  facile  introduction  to  the  cavity  of  decay. 

The  pellet  should  then  be  taken  by  a  pair  of  foil-pliers  and 
placed  in  the  prepared  cavity. 

The  filling  should  be  introduced  by  appropriate  smooth,  ilat, 
or  round-ended  instruments,  which  may  be  found  in  Nos.  2,  3, 
5,  6,  7,  and  8  of  the  set  of  amalgam  filling  instruments. 

The  filling  should  be  worked  into  place,  and  the  condensation 
of  the  material  effected  by  pressure  of  the  face  of  the  filling  in 
precisely  the  same  manner  as  is  done  with  soft  foil,  with  the 
exception  that  the  same  smooth-faced  instruments  should  be 
used  instead  of  pointed  or  serrated  fillers. 

It  will  be  found  advantageous  to  touch  the  faces  of  the  in- 
struments to  an  "oil-pad," — see  Gutta-percha, —  as  this  pre- 
vents adhesion  to  them  of  the  filling  material;  particularly 
is  this  useful  in  filling  approximal  cavities  and  in  "  facing " 
built-up  crowns. 

The  superfluous  portions  of  the  mass  —  should  there  be  any 
—  ought  to  be  so  manipulated  as  that  they  will  overhang  the 


ZINC-PHOSPHATE.  171 

edges  of  the  cavity.  When  this  is  done,  they  readily  break 
away,  leaving  the  filling  nicely  adapted  to  the  walls  of  the 
cavity,  and  it  also  secures  a  smooth,  compressed  surface  to  the 
filling. 

In  filling  large,  difficult,  and,  in  a  measure,  inaccessible  cavi- 
ties, it  is  essential  to  good  results  that  several  mixing^  should 
be  made,  each  of  the  various  portions  being  introduced  separately, 
and  manipulated  just  like  a  pellet  of  soft  foil. 

In  cavities  between  teeth  which  extend  up  to,  and  particu- 
larly under,  the  gum,  it  is  necessary  to  fill  out  to  the  cervical 
edge  and  downward  for  at  least  one-third  of  the  cavity  with 
gutta-percha,  as  a  double  preventive  to  decay  of  the  tooth  and 
disintegration  of  the  zinc-phosphate. 

NOTE. — The  disintegration  of  oxy-chloride  of  zinc  at  the  cervical  portion  of 
the  filling  has  been  referred  to  ;  and  it  will  therefore  only  be  necessary  to  men- 
tion that  zinc-phosphate  has  the  same  peculiarity,  but  in  less  degree.  It  is,  how- 
ever, sufficiently  vulnerable  at  that  point  to  render  it  imperative  that  a  "  guard  " 
of  gutta-percha  or  submarine  amalgam,  according  as  the  tooth  is  more  or  less 
conspicuous,  should  be  first  introduced. 

After  the  introduction  of  the  filling,  it  should  be  kept  dry 
for  at  least  Jive  minutes.  It  should  then  be  varnished,  and  the 
varnish  be  allowed  to  dry  thoroughly.  If  it  is  not  easily  prac- 
ticable to  maintain  the  five  minutes  of  dryness,  the  filling  should 
be  varnished  immediately  upon  completion. 

If  any  further  finishing — for  articulation,  etc.  —  is  required, 
the  filling  should  be  allowed  to  harden  for  at  least  thirty  min- 
utes—  longer  time  is  better,  if  possible  —  before  this  is  done; 
after  which  it  should  again  be  varnished  as  before. 

Varnish  for  this  purpose  may  be  made  from  any  of  the  fol- 
lowing formulae : 

R     Absolute  Alcohol f3i. 

Gum-Saiidanic  ) 

/    i     .  j  .        >  r errs.  xxx. 

(selected  tears)) 

A  good  varnish,  but  slow  dryer. 

B     Sulphuric  Ether f3i. 

Gum  Copal grs.  xxx. 

A  good  varnish  and  quick  dryer,  but  disagreeably  odorous  to  some. 


172  PLASTICS    AND    PLASTIC    FILLING. 

B  .  Methylic  Alcohol f  5i. 

Gum-Sandarac grs.  xxx. 

A  good  varnish,  and  reasonably  quick  dryer. 
,^» 

In  finishing  "zinc-phosphate"  fillings,  cutting  instruments  — 
like  NoJ9,  for  example — files,  burrs,  stones,  and  disks  are  ad- 
missible. When  files  or  burrs  are  used,  they  should  be  either 
perfectly  dry  or  thoroughly  wet ;  as  these  conditions,  in  great 
degree,  prevent  them  from  becoming  clogged. 

The  face  of  the  filling  is  better  if  burnished  after  it  is  thor- 
oughly hardened.  For  this  purpose  a  steel  or  agate  burnisher 
can  be  used.  If  the  face  of  the  filling  is  marked  from  using  a 
steel  burnisher,  it  is  readily  cleaned  with  pulverized  pumice  on 
a  soft  pine  stick. 

It  seems  proper  that  a  few  final  directions,  or  rather  sugges- 
tions, should  be  given  with  a  view  to  completeness  rather  than 
importance. 

In  taking  the  "crystals"  from  the  bottle,  it  is  far  better 
that  sufficient  be  scraped  up  and  shaken  or  turned  out  into  a 
spoon,  than  that  the  contents  of  the  bottle  be  warmed  by  placing 
it  in  h'ot  water ;  as  every  such  heating  is  eminently  detrimental 
to  a  good  crystal.  Ordinary  crystals  it  does  not  appear  to  injure 
much,  if  any;  for  they  continue  to  make  cement  about  as  at 
first. 

In  taking  "fluid"  from  the  bottle,  it  is  better  to  use  a  small 
piece  of  stick  dipped  into  it,  as  this  method  is  most  accurate 
and  economical.  A  fresh  piece  of  stick  should  be  used  for  the 
making  of  each  filling,  as  the  portion  of  menstruum  remaining 
adherent  to  it  from  time  to  time  is  liable  to  hasten  markedly 
the  deterioration  of  most  fluids. 

It  has  been  directed  that  "  more  than  sufficient "  powder 
should  be  poured  out  preparatory  to  mixing  the  mass.  The 
reason  for  this  is,  that  even  a  respectably  good  zinc-phosphate 
will  "  set "  so  promptly  as  to  require  that  no  time  be  needlessly 
lost  in  its  preparation  and  insertion,  which  would  necessarily 
be  the  case  if  one  were  obliged  to  stop  and  replenish  the  stock 
of  powder. 

In  returning  the  surplus  powder  after  filling,  care  is  requisite 
not  to  return  any  which  has  been  touched  by  the  fluid. 


ZINC-PHOSPHATE.  173 

It  is  sufficient  to  say  that  no  menstruum,  either  crystal  or 
fluid,  should  be  used  after  it  ceases  to  make  a  cement  which 
will  respond  to  the  "  tests  "  for  goodness.  , 

The  best  method  for  removing  from  the  fingers  such  portions 
of  zinc-phosphate  as  may  adhere  to  them,  is  by  rubbing  them, 
while  wet,  with  the  edge  of  the  glass  mixing-slab. 

For  the  removal  of  adherent  material  from  the  slab,  the 
spatula  will  prove  convenient  and  effective  —  scraping  the  slab 
while  holding  it  in  a  stream  of  water. 

In  removing  and  replacing  the  corks  from  both  menstruum 
and  powder  bottles,  it  is  better  to  twist  them  slowly  and  stead- 
ily, always  to  the  right,  as  this  will  prevent  breaking  thcrn. 

Conclusions. —  In  estimating  the  value  of  zinc-phosphate  ce- 
ments, I  have  realized  that  much  discount  must  be  made  upon 
the  statements  of  most  of  those  who  manufacture  a*id  dispense 
them.  They  have  already  been  invested  with  such  names  as 
indicate  gradations  of  obduracy  from  porcelain  to  adamant, 
but  I  do  not  think  the  provings  will  rank  any  such  appella- 
tions as  appropriate,  or,  indeed,  as  anything  but  deceptive. 

Zinc-phosphate  cannot  be  regarded  as  an  "  insoluble  "  cement, 
but  must  be  accepted  as  "not  very  soluble"  in  the  fluids  of  the 
mouth.  It  can,  however,  be  graded  as  much  better  than  oxy- 
chloride  of  zinc. 

It  can,  in  no  wise,  be  esteemed  as  even  a  moderate  approach 
to  the  "  ideal  filling  material,"  for,  although  it  possesses  many 
of  the  desired  attributes,  it  is,  nevertheless,  deficient  in  a  suf- 
ficient number  of  them  to  place  it  entirely  without  the  pale  of 
consideration  in  this  regard.  It  has  not  only  been  suggested, 
but  strongly  recommended  as  a  "pulp-capper,"  and  this  merelv 
because  it  does  not  irritate  that  organ ;  but  it  must  be  remem- 
bered that  a  material  may  be  non-irritant  and  yet  be  eminently 
capable  of  pulp  devitalization — vide  Cadmium;  therefore,  I 
have  always  warned  my  classes  against  this  use  of  the  material 
until  it  has  been  proven,  by  careful,  patient  experimentation,  to 
be  worthy  of  reliance  in  this  particular,  and  up  to  this  time 
my  own  convictions  are  rather  adverse  than -favorable  to  its 
claims. 

It  seems  to  be  especially  adapted  for  articulating,  approximal 
— under  guarding  —  and  labial  cavities  in  frail,  pulpless  teeth  ; 


PLASTICS    AND    PLASTIC    FILLING. 

or  in  teeth  containing  vital  pulps,  with  these  thoroughly  pro- 
tected by  zinc-sulphate  or  gutta-percha ;  and  in  such  cases  it 
has  stood  the  "  oral  test "  for  nearly  three  years  in  a  remark- 
ably satisfactory  manner  for  a  zinc  plastic. 

I  am  experimenting  with  it  as  a  "liner"  for  frail  teeth  which 
are  to  be  filled  with  amalgam,  and  thus  far  it  promises  well. 

It  will  now  be  seen  that  from  the  plastic  stand-point,  while 
there  exists  no  such  use  for  zinc-phosphate  as  would  warrant 
any  immediate  considerable  demand,  it  is,  nevertheless,  an  im- 
portant and  satisfactory  adjunct,  and  one  that  will  meet  the  re- 
quirements of  certain  cases,  which,  without  it,  would  be  almost 
insurmountable. 


ARTICLE   XVII. 
TEMPORARY  STOPPING. 

A  MATERIAL  for  this  purpose  has  been  suggested  to  me, 
which  I  deem  worthy  of  especial  notice.     It  is  a  mixture 
of  red  gutta-percha  base-plate,  white  wax,  silex,  and  feldspar. 

In  a  sand-bath,  over  a  spirit-lamp,  place  a  small  glass  beaker 
or  other  convenient  vessel.  In  this  melt  two  pennyweights  of 
white  wax.  When  this  is  melted,  add  to  it  six  pennyweights 
of  gutta-percha  base  plate,  cut  into  small  pieces ;  when  this  is 
melted,  add  three  pennyweights  of  finely  pulverized  silex  and 
three  pennyweights  of  powdered  feldspar.  Stir  all  thoroughly 
together  and  let  the  mixture  partially  cool.  When  the  mass 
becomes  doughy,  press  it  between  two  plates  of  glass,  first  wet- 
ting them  to  prevent  adhesion.  This  compound  fulfils  the  re- 
quirements of  a  "temporary  stopping"  more  acceptably  than 
any  other  which  I  have  ever  used. 


TECHNICALITIES.  175 

ARTICLE  XVIII. 
TECHNICALITIES. 

AS  in  the  progress  of  the  development  of  plastic-filling  ma- 
terials, instruments  for  manipulation,  apparatus  for  testing 
and  experimentation,  and  methods  for  utilization  have  been  de- 
vised, and  substances  —  metallic,  organic,  and  inorganic  —  have 
been  brought  into  service,  so  has  it  been  found  needful  to  coin 
a  technical  phraseology  by  which  explanations  could  be  made ; 
comparison  of  views  be  indulged  in  ;  methods  referred  to  ;  and 
advantages  and  disadvantages  of  operations  be  discussed,  con- 
cisely, definitely,  and  intelligibly. 

So  strangely  apathetic  have  been  the  reputed  leaders  in  den- 
tistry, that,  notwithstanding  the  constant  reference  to  these 
terms  which  has  necessarily  been  made  in  practice,  as  repeated 
demonstration  of  power  to  cope  with  things  impossible  of  ac- 
complishment by  any  previous  materials  and  methods  has  been 
given,  and  although  attention  has  been  directed  to  them  by 
public  and  careful  enunciation,  they  have,  up  to  this  present, 
remained  terms  possessed  of  meaning  to  but  few,  and  these, 
with  rare  exceptions,  from  among  the  younger  and  rising  mem- 
bers of  our  profession. 

It  is  noted  in  journal  communications  that  an  occasional  use 
of  plastic  phraseology  is  indicative  of  commencing  acceptation, 
and  it  is  now,  beyond  question,  a  matter  of  immediate  import 
that  those  who  purpose  saving  the  teeth  of  the  coming  generation, 
should  familiarize  themselves  with  the  technicalities  of  that 
practice  which  alone  has  demonstrated  a  reasonable  capability 
for  the  attainment  of  this,  much  to  be  desired,  result. 

Ageing. —  This  term  is  applied  to  certain  changes  which 
occur  to  almost  every  variety  of  every  plastic-filling  material. 
It  is  also  used  to  express  the  attainment,  by  any  means,  of  re- 
sults which  are  given  by  time,  and  which  are  regarded  as  de- 
sirable ;  as,  for  instance,  the  "  ageing  "  of  gutta-percha  is  recog- 
nized as  detrimental,  in  that  the  material  becomes  brash,  losing 
its  toughness  ;  it  becomes  easily  disintegrated  by  attrition  and 
by  the  fluids  of  the  mouth;  it  is  crumbl}- — indisposed  to  co- 
here; it  is  "time-rotted."  Oxy-chloride  of  zinc  powder  loses 


176  PLASTICS    AND    PLASTIC    FILLING. 

its  sharpness  of  response  in  setting  and   also  its  density  and 
hardness,  becoming  slow-setting,  porous,  and  soft. 

The  fluids  and  syrups  of  oxy -phosphates,  and  the  fluids, 
syrups,  pastes,  and  crystals  of  zinc-phosphates,  as  a  rule,  lose 
their  value  entirely  from  "ageing,"  and  those  which  do  not, 
have  equally,  as  a  rule,  but  modified  value  at  any  time  when 
compared  with  an  "  excellent  "  menstruum. 

Amalgam  alloys,  on  the  contrary,  after  being  cut  or  filed, 
improve  notably  from  "  ageing."  Amalgams  made  from  really 
good  alloys  are,  without  exception,  very  much  better  after 
these  have  been  filed  up  for  several  months.  Ordinary  alloys 
work  better  when  "aged  "  than  they  do  when  "fresh,"  but  the 
better  the  alloy  the  more  marked  is  the  improvement  due  to 
"  ageing."  They  work  much  more  smoothly,  require  less  mer- 
cury, set  more  slowly  and  yet  with  sufficient  celerity,  and,  under 
every  "  test,"  become  more  desirable. 

Reference  has  been  made  to  the  fact  that,  in  considerable 
degree,  this  effect  of  time  upon  cut  or  filed  alloj-  may  be  pro- 
duced by  continued  attrition  of  particles,  or  by  repeated  ex- 
posure of  particles  to  the  air,  or,  most  probably,  by  a  combina- 
tion of  both.  This  is  done  by  placing  the  filings  in  a  cylinder 
of  glass,  and  causing  it  to  revolve  with  moderate  speed  for  the 
space  of  several  hours,  and  the  process  is  called  "  ageing  the 
filings." 

Bulging. — By  this  is  meant  a  change  of  shape  which  takes 
place  in  amalgam,  and  by  which  the  form  of  a  filling  is  so 
altered,  from  spheroiding,  as  to  present  a  modified  convexity 
of  face.  This  result  is  attributed  to  the  spheroidal  control  of 
the  mercury,  and  is  more  pronounced  as  the  metals  of  which 
the  alloy  is  composed  are  more  yielding  in  texture,  less  obdurate 
in  melting,  and  more  deliberate  in  cooling.  The  concomitant 
<tf  bulging  is  crevicing,  as,  in  the  attainment  of  a  spheroidal 
form,  the  filling  material  is,  necessarily,  drawn  from  such  cav- 
ity-edges as  have  had  to  be  left  straight  instead  of  curved  — 
concave. 

This  term  is  also  applied  to  the  softening  and  swelling  out 
which  sometimes,  though  very  rarely,  occurs  in  fillings  of  gutta- 
percha —  notably  red  gutta-percha,  or  lase-plale.  This  result  is 
generally  attributed  to  inferiority  of  material ;  but,  though 


TECHNICALITIES.  177 

this  may  be  usually  a  correct  ascribing,  I  am  inclined  to  the 
opinion  that,  in  some  mouths,  it  will  occur  with  the  very  best 
gutta-percha. 

Buffering. — This  word  is  used  to  denote  an  operation  by 
means  of  which  a  yielding  material,  like  gutta-percha,  is  pro- 
tected from  attrition  by  a  more  or  less  resistant  material,  like 
zinc-phosphate  or  amalgam.  It  signifies  protection  from  blows 
or  frictional  impinging,  and  is  the  method  \>y  which  the  plastic- 
filler  is  enabled  to  utilize  the  tooth-saving  power  of  gutta- 
percha  in  frail  bicuspids  and  molars  in  which  are  cavities  of 
decay  extending  up  to  and  under  the  gum,  and  opening  through 
upon  the  articulating  faces  of  the  teeth.  The  "  buffer  "  is  gen- 
erally trunnioned  either  in  dentine  or  zinc-chloride,  though 
sometimes  an  acceptable  retaining  shape  can  be  given  to  the 
articulating  cavity-edge. 

Capping. — As  used  with  reference  to  filling,  this  word  implies 
completely  outside  work,  in  contradistinction  to  the  completely 
inside  work  of  pulp-capping.  Whereas,  the  latter  is  done  with 
the  softest  and  most  yielding  materials  used  in  plastic  dentistry, 
the  former  is  done  only  with  those  possessing  markedly  the 
characteristic  of  resistance  to  attrition.  It  is  used  to  express 
the  thin  covering  of  a  yielding  material  with  which  a  "tap" 
for  future  "venting"  may  be  filled.  This  is  usually  gutta- 
percha,  a  materia*!  which  must  be  protected  if  the  "  tap  "  has 
to  be  made  upon  any  surface  exposed  to  attrition.  The  capping 
is  done  either  with  zinc-phosphate  or  amalgam,  and  if  with  the 
latter,  "facing''  amalgam  is  usually  employed,  as,  by  its  marked 
retention  of  color,  the  position  of  the  "  tap  "  is  indicated. 

Coll- Soldering. — This  phrase  is  used  to  express  one  of  the 
most  useful  possibilities  in  connection  with  plastic  filling.  It 
is  a  property  of  amalgam,  that  additions  of  this  material  can  be 
secured  firmly  and  homogeneously  to  either  gold  or  amalgam  fill- 
ings, whether  they  be  old  or  of  recent  introduction.  In  this  wav 
old  fillings  are  joined  on  to  and  made  subservient  for  retaining 
purposes,  in  cases  of  new  decay — shallow  cavities — encroaching 
upon  or  approaching  near  to  such  fillings.  Large  reparations 
are  made  with  perfect  facility  in  cases  where  masses  of  tooth- 
structure  have  been  broken  away  from  heavily-filled  teeth. 
Fillings  are  made  to  present  the  appearance  of,  and  to  be,  prac- 
12 


178  PLASTICS    AND    PLASTIC    FILLING. 

tically,  one  large  filling,  by  merely  removing  the  carious  tissue 
from  between  them  and  joining  them  with  new  filling  material 
—  amalgam. 

Pins  for  pivoting  are  fixed  in  position  by  drilling  oval  drill- 
holes in  amalgam  root-fillings,  and  securing  the  pins  with  freshly- 
made  amalgam. 

Gold  bands  are  held  firmly  upon  crownless  roots  by  filling 
the  canals  with  amalgam  and  cold -soldering  the  bands  by 
building  up  amalgam  crowns  within  them. 

Linings  of  amalgam  are  placed  in  cavities  of  doubtful  teeth, 
which  are  thus  secured  against  decay,  and,  after  many  days,  if 
results  are  unfavorable,  this  thin  stratum  of  filling  is  readily 
removed.  If,  on  the  contrary,  the  result  is  favorable,  the  re- 
maining portion  of  filling  is -just  as  readily  added  on. 

Crowns  are  partially  built  up,  and  if  circumstances  —  such 
as  want  of  time  for  completion  of  operation  ;  urgent  demand 
for  services  by  other  patients,  etc., —  compel  cessation  of  work, 
it  is  a  matter  of  no  moment  so  far  as  any  complication  is  con- 
cerned, for,  at  any  time,  the  work  may  be  resumed  just  as  if 
it  had  not  been  interrupted.  All  these,  and  many  other  re- 
quirements equally  convenient  to  meet  and  desirable  to  avail 
one's  self  of,  are  boons  bestowed  alike  upon  patient  and  opera- 
tor by  "cold-soldering." 

As  in  all  soldering  the  face  of  the  metal  to  be  soldered  upon 
must  be  made  bright  either  by  scraping  with  an  excavator, 
smoothing  with  a  file,  or  cutting  with  a  burr-drill;  a  small 
portion  of  amalgam  is  then  mixed  very  soft,  arid,  being  placed 
upon  the  brightened  surface,  is  rubbed  over  it  until  it  is  thor- 
oughly "amalgamated,"  after  which  all  superfluous  amalgam 
should  be  removed.  Having  thus  obtained  a  soldering  surface, 
the  appropriate  amalgam  —  indicated  by  the  position  of  the 
cavity  or  the  exigencies  of  the  case  —  should  be  mixed  as  usual, 
and  the  filling  made.  The  necessary  caution  in  regard  to  care 
in  using,  if  such  is  required,  should  not  be  forgotten,  and,  with 
such  admonition,  the  patient  can  be  assured  that  upon  the  com- 
plete hardening  of  the  filling  material  a  result  will  have  been 
attained  which,  in  strength,  durability,  and  homogeneity,  will 
be  precisely  the  same  as  though  the  filling  had  been  originally 
made  with  its  present  contour  and  dimensions. 


TECHNICALITIES.  179 

Oreviciny. —  This  word  is  used  to  express  that  result  referred 
to  under  "  bulging,'1  when  an  amalgam  filling  has  assumed  such 
shape,  from  tendency  to  spheroid,  as  to  have  drawn  from  the 
margins  of  the  cavity.  It  is  probable  that  more  amalgam  fill- 
ings have  been  unjustly  condemned,  as  worthless,  from  this 
"  crevicing  "  than  from  any  other  cause.  So  far  from  being  a 
serious  and  irremediable  defect,  it  is  most  frequently  very  easily 
and  quickly  removed,  and,  by  its  removal,  a  filling  of  great 
value  is  secured. 

The  removal  is  effected  either  by  filing,  stoning,  or  burring 
off  the  superfluous  amalgam  ;  and  a  filling  is  thus  again  brought 
into  contour  with  the  cavity  edges,  which,  having  bulged  in 
one  direction  —  outwardly  —  has  likewise,  from  the  same  cause, 
become  even  more  accurately  than  ever  in  apposition  with  the 
cavity  walls.  Besides  this,  the  filling  is  usually  an  old  one,  or, 
at  least,  one  of  several  years'  duration,  and,  during  all  the  time, 
a  formation  of  sulphides  has  been  progressing,  which,  by  im- 
pregnation of  contiguous  dentine,  has  rendered  that  tissue  of 
most  congenial  potentiality  with  the  surface  of  the  filling.  All 
this  harmonious  condition  of  things  has  been  reached  by  that 
gentle  gradation  of  change  which  the  experience  of  many  years 
proves  to  be  productive  of  extraordinary  permanency. 

It  may,  therefore,  well  be  questioned  as  to  whether  the  re- 
moval of  such  fillings  is  not  alone  of  doubtful  benefit ;  but,  far 
more  than  this,  acts  of  positive  wrong  to  patients  —  work  which 
it  behooves  every  conscientious  practitioner  to  weigh  well  be- 
fore continuing  in  the  stereotyped  condemnation  based  upon 
convictions  which  time  has  shown  to  have  been  founded  upon 
prejudice  alone. 

If  crevicing  is  of  such  depth  as  to  render  the  removal  of  a 
superficial  stratum  of  amalgam  insufficient  to  restore  to  the 
filling  a  desirable  perfection,  it  is  proper  that  a  groove  or  canal 
should  be  cut,  with  an  oval  burr  or  fissure-drill,  throughout 
the  length  of  the  crevice.  This  groove  should  then  be  filled 
with  freshly  made  amalgam,  which,  as  has  been  stated,  will 
unite  homogeneously  with  the  former  filling. 

It  is  frequently  possible,  at  the  present  time,  to  very  much 
improve  the  appearance  of  these  creviced  amalgam  fillings  by 
cutting  out  a  thin  stratum  of  the  old  amalgam,  and  replacing 


180  PLASTICS    AND    PLASTIC    FILLING. 

it  with  one  of  the  good  color  keepers,  either  "contour"  or 
"  contour  "  and  ''  facing,"  half  and  half,  or  even,  in  rare  cases, 
where  edge-strength  is  of  no  special  consideration,  with  "facing" 
amalgam  alone. 

Domeing. — This  operation  consists  in  building  up  a  pointed 
or  conical  dome  of  gutta-percha  from  the  pulp-cavity  towards 
that  portion -of  the  periphery  of  a  filling  at  which  it  would  be 
proper  to  "  tap  "  if  crown-tissue  were  existent.  Having  thus 
formed  this  "dome,"  the  filling,  of  amalgam,  is  made,  and  the 
point  of  the  dome  covered  in.  If  at  any  future  time  it  becomes 
advisable  to  enter  canals,  the  entrance  is  easily  made  by  drilling 
through  the  thin  covering  of  amalgam,  and  removing  the  gutta- 
percha  by  means  of  a  warmed  instrument  or  small  oval  burr. 
The  entrance  having  been  effected,  and  the  desired  relief  hav- 
ing been  given,  the  matrix  left  by  the  removal  of  the  dome  is 
readily  refilled,  and  the  position  of  the  tap  made  perfectly  ap- 
parent by  capping  with  facing  amalgam. 

For  superior  molars,  the  dome  should  point  towards  the  centre 
of  the  articulating  faces;  for  inferior  molars,  the  dome  should 
point  mGsio-buccally .  Molars  are  the  only  teeth  which  it  is 
ever  necessary  to  dome. 

Facing. — In  "  facing,"  we  have  the  aesthetic  of  plastic  den- 
tistry. It  is,  in  the  direction  of  beauty,  that  which  cold- 
soldering  is  in  the  direction  of  utility.  Facing  is  done  with 
gutta-percha,  zinc-phosphate,  and  amalgam ;  the  incisors  and 
cuspids  either  with  gutta-percha  or  zinc-phosphate,  the  bicus- 
pids and  molars  usually  with  amalgam,  exceptionally  with 
gutta-percha. 

Facing  is  of  two  grades, — the  facing  of  fillings  and  the  facing 
of  "built-up"  teeth.  The  first  is  of  comparatively  circum- 
scribed extent,  and  is  done  in  cases  where  decay  has  progressed 
in  such  manner  as  to  impinge  upon  the  labial  faces  of  incisors 
and  cuspids.  Cavities  in  these  teeth  having  been  properly 
lined,  if  necessary,  and  filled  in  contour  with  contour  amalgam, 
the  filling  is  allowed  to  harden  for  about  thirty  minutes,  after 
which  it  is  cut  into  with  the  trimmer  from  the  front.  The  ex- 
cavation is  bounded  by  the  remaining  labial  enamel  on  the  one 
side  and  by  the  contour-line  of  the  filling  on  the  other.  The 
slot  thus  cut  out  is,  in  this  way,  made  of  the  exact  shape  of  the 


TECHNICALITIES.  181 

missing  portion  of  enamel,  and  the  slotted  filling  is  then  allowed 
to  harden  thoroughly  —  an  hour  or  more. 

If  it  is  desirable  to  avoid  retaining  the  patient  longer  at  this 
sitting,  the  slot  may  be  filled  temporarily  with  low-heat  gutta- 
percha.  This  is  not  sufficiently  resistant  to  endanger  the  frail, 
bevelled  edges  of  the  newly-made  amalgam  on  the  contour  edge. 
The  slot  should  be  finally  filled  either  with  facing  gutta-percha 
(gutta-percha,  1  part ;  oxide  of  zinc,  6  J  or  7  parts)  or  with  zinc- 
phosphate,  by  making  the  shade  desirable.  Both  gutta-percha 
and  zinc-phosphate  may  be  shaded  yellowish  by  the  addition  of 
a  little  chrome-yellow,  and  bluish  by  the  addition  of  a  VERY  little 
lamp-black. 

These  gutta-percha  facings  can  readily  be  made  to  match  the 
color  of  the  teeth  so  closely  as  not  to  attract  the  least  attention. 
They  are  quite  durable,  lasting  frequently  for  several  years, 
and  are  renewed  at  any  time,  if  required,  in  a  few  minutes. 

The  zinc-phosphate  facings  are,  as  yet,  more  experimental,  but 
I  have  a  goodly  number  which,  during  the  past  three  years,  have 
proven  eminently  satisfactory.  I  never  use  a  zinc-phosphate 
for  facing  unless  it  responds  well  to  all  the  tests  given  for 
"  good "  material,  and  I  am  very  careful  to  maintain  dryness 
during  filling  and  setting, —  usually  with  rubber-dam, —  and  to 
varnish  thoroughly,  and  to  let  the  varnish  dry  completely. 

In  facing  "built-up"  crowns,  it  is  first  essential  that  the  crown 
be  built  perfectly  with  contour  amalgam.  In  no  other  way  can 
the  contour-lines  for  facing  be  attained  with  any  degree  of  accu- 
racy or  beauty.  In  the  first  building  the  whole  anatomy  and 
expression  of  the  crown  can  be  given,  and  the  proper  articula- 
tion is  secured.  The  result  is  a  crown  which,  for  size,  appear- 
ance, strength,  and  utility,  would  be  all  that  could  be  desired  ; 
but  the  insuperable  objection  to  such  a  crown  is,  that  it  will 
probably  change  to  a  color  worse  even  than  that  of  gold.  To 
obviate  this,  the  buccal  face  of  the  crown  is  concaved  most 
delicately,  most  accurately,  and  artistically.  This  is  no  easy 
task ;  for  the  slightest  slip  of  the  trimmer  or  excavator,  and, 
above  all,  the  least  mal  a  propos  whirl  of  the  burr-drill,  will 
mar  the  beauty  of  the  contour-lines. 

The  concavity  being  made,  if  it  is  to  be  filled  with  facing 
amalgam, —  tin,  silver,  gold,  and  zinc, —  the  work  can  be  well 


182  PLASTICS    AND     PLASTIC     FILLING. 

done  immediately,  and,  for  a  vast  majority  of  cases,  I  prefer 
this  facing  to  any  other,  as  the  built-up  crowns  appertain, 
almost  exclusively,  to  bicuspids  and  molars,  which,  with  such 
facings,  almost  always  make  very  presentable  and,  indeed, 
pretty  operations. 

But  it  is  nevertheless  true  that,  occasionally,  facing  amalgam 
will  discolor,  and  it  is  for  this  reason  that  we  sometimes  have 
to  resort  to  the  gutta-percha  and  zinc-phosphate  facings  for 
bicuspids.  When  this  is  so,  the  concavities  should  be  made 
much  deeper  then  is  needed  for  the  using  of  amalgam,  and  me- 
chanical retaining-slots,  grooves,  or  undercuts  should  be  made 
for  the  securing  of  the  facing. 

In  these  cases  gutta-percha  has  made  a  good  record,  usually 
doing  service  for  from  two  to  five  years,  and  then  requiring  but 
a  thin  film  of  additional  facing. 

Much  thought,  labor,  and  experimentation  has  been  bestowed 
upon  the  accomplishment  of  this  desideratum  in  plastic  work, 
and  the  results  have  been  such  as  to  cause  the  plastic-fillers  to 
feel  well  compensated  for  all  their  toil. 

But  the  satisfaction  of  the  workers  have  been  a  slight  thing 
in  comparison  with  the  outpourings  of  delight  and  gratitude 
which,  have  come  from  patients,  especially  lady  patients,  who 
have  seen  their  frail  but  beautiful  "  pearls  "  crumble  away  from 
"the  jewels  of  gold,"  until,  while  yet  in  young  life,  they  had 
come  to  smile  smiles  of  barbaric  magnificence  as  the  "ruby 
portals  "  revealed  a  terrible  preponderance  of  the  brilliant  tri- 
umphs of  "first-class"  dentistry. 

These  are  the  dentures  which,  taken  after  the  dropping  out 
of  the  third  or  fourth  line  of  such  work,  after  the  expenditure 
of  dollars  by  the  hundred  until  the  hundreds  had  wellnigh 
reached  a  thousand,  after  the  remnants  had  come  to  be  a 
jagged  row  of  roots  and  broken  cusps  and  edges,  have  been  so 
"  built  up  "  and  "  faced  "  as  to  have  in  such  degree  restored  the 
original  beauty  of  expression  to  their  possessors,  that  words 
seemed  inadequate  to  do  their  feelings  justice,  and  written 
praises  have  blessed  the  day  on  which  they  learned  of  plastic 
dentistry. 

Frotting. —  This  term  is  from  the  French,  "  frotter,"  and  sig- 
nifies "  to  rub."  It  is  applied  to  the  method  by  which  certain 


TECHNICALITIES.  183 

kinds  of  plastic  materials  are  tested  for  "probable  wear.'' 
These  are  oxy-chlorides,  oxy-phosphates,  and  zinc-phosphates. 
The  illustration  of  the  machine  for  "fretting"  will  give  so 
clear  an  idea  of  its  working  as  to  need  no  description,  and  it 
will  therefore  suffice  for  me  to  say  that  pellets  of  the  materials 
to  be  tested  are  made  into  pill  form  and  placed  in  a  small  tube 
containing  water,  slightly  acid,  slightly  alkaline,  or  neutral, 
and  are  then  frotted  by  the  pendulum-like  motion  given  to 
the  tube  by  wheels  arranged  like  clock-works  and  driven  by 
a  powerful  spring. 

In  this  manner  the  relative  durability  of  such  plastics  as 
disintegrate  in  the  fluids  of  the  mouth  is  quickly  tested,  and 
quite  a  number  of  materials,  which,  from  the  enthusiastic  and 
emphatic  assertions  of  their  makers,  would  have  given  rise  to 
costly  and  tedious  lines  of  disappointing  experimentation,  have 
been  strangled  almost  at  their  birth. 

Guarding. —  For  many  years  it  has  been  noted  that  fillings 
are  prone  to  fail  at  the  cervical  edge.  So  frequently  is  this  the 
case,  that  this  part  of  the  cavity  wall  has  come  to  be  known 
as  "  the  vulnerable  spot."  In  foil  practice,  this  failure  has  ever 
been  attributed  to  "defective  manipulation;"  but  this  reasoning 
has  always  been  a  matter  for  peculiar  comment  upon  the  part 
of  the  plastic-fillers,  and  the  explanation  has  been  regarded  by 
them  as  not  at  all  satisfactory.  They  have  thought  it  strange 
that  the  easiest  part  of  the  foil-filler's  work  —  the  introduction 
of  the  foundation  or  first  pieces  —  should  have  been  so  uni- 
versally ladly  done.  They  have  thought  that,  of  all  the  fill- 
ing, the  cervical  portion  would  be  the  best,  and  that,  in  conse- 
quence, it  should  the  least  permit  recurrence  of  decay.  They 
have  noted  the  same  unsatisfactory  results  at  the  cervical  mar- 
gins of  cavities  filled  with  plastic  fillings,  and  they  could  not 
ascribe  these  failures  to  "  defective  manipulation ;  "  for  they 
kneiu  the  manipulation  of  the  filling  material  at  this  point  was 
as  perfect  as  it  possibly  could  be.  They  knew  that  .there  was 
no  "loosening  of  the  first  pieces;"  no  "slipping  of  the  first 
layer;  "  no  "leakage  from  turning;  "  no  "crumbling  of  cavity 
walls  from  malleting ;  "  and  yet  they  knew  that  the  vulnerable 
spot  existed  for  them  just  the  same  as  it  did  for  the  "defective 
manipulators." 


184  PLASTICS     AND    PLASTIC    FILLING. 

It  has  also  been  observed  that  by  far  the  most  frequent  and 
most  extensive  cavities  of  recurring  decay  are  found  in  con- 
nection with  gold-fillings ;  that  second  in  relative  proportion, 
numerically,  the  cervical  edge  of  cavities  is  vulnerable  under 
tin  and  silver  amalgams;  that  it  is  vulnerable  in  third  degree 
under  fillings  of  tin-foil,  or  of  silver,  tin,  and  copper  amalgams ; 
that  it  is  still  less  vulnerable  —  in  fourth  degree  —  under  gutta- 
percha  fillings;  and  that  here  the  grades  of  vulnerability  of 
cervical  tooth-bone  cease. 

And  now,  it  has  been  noted  that,  although  recurrence  of  cav- 
ity formation  continues,  it  does  so  at  the  expense  of  filling 
materials  instead  of  tooth-bone.  The  fillings  of  oxy-chloride 
of  zinc,  oxy-phosphate  of  zinc,  and  of  zinc-phosphate,  in  the 
order  given,  disintegrate  at  their  cervical  margins ;  the  first, 
notably;  the  second  quite  promptly,  and  the  third,  though 
much  more  durable,  far  too  quickly. 

To  the  mind  of  a  plastic-filler  the  "  defective  manipulation  " 
theory  offers  no  explanation  whatever  of  all  this:  but  with  the 
Palmer  theory  of  relative  consonance  of  potential,  or  "compat- 
ibility between  filling  material  and  tooth-bone,"  everything 
seems  clear  and  easy  of  explanation. 

It  is  understood,  by  consent,  that  all  substances  have  a  defi- 
nite molecular  motion  which  is  expressed  by  the  word  "poten- 
tial." It  is  proven  by  galvanometric  experiments  that  contact 
between  almost  any  two  substances  —  using  the  word  in  its 
general  sense  —  develops  electrical  phenomena. 

It  is  agreed  that  needle  deflection  denotes  difference  in  po- 
tential between  substances  just  in  proportion  to  the  magnitude 
of  the  deflection. 

It  is  agreed  that  in  proportion  to  difference  in  potential  so  will 
contact  of  substances  produce  electrical  and  chemical  results. 

It  is  agreed  that  one  of  the  substances  becomes  positive  to 
the  other,  and  that  the  other  becomes  negative  to  the  first. 

It  is  agreed  that,  under  the  action  excited  by  contact,  the 
substance  which  is  proven  to  be  positive  is  markedly  disinte- 
grated, and  it  is  inversely  deduced  that  disintegration  of  sub- 
stance proves  positivity  to  that  substance. 

It  is  agreed  that  moisture  increases  most  notably  the  rapid 
ity  and  extent  of  this  disintegration ;  and,  that  moisture  pos 


TECHNICALITIES.  185 

sessed  of  certain  characteristics  which  render  it  neutral — as  it 
is  termed — least  facilitates  this  action;  while  moisture  pos- 
sessed of  other  characteristics  —  acidity,  alkalinity,  etc.,  —  most 
promotes  it. 

Thus  far  all  is  clearly  scientific,  and  the  plastic-fillers  accept 
this  as  a  basis  upon  which  to  offer  an  explanation. 

They  find  aid  in  this  matter  from  observation  of  filling  ma- 
terials in  their  relation  to  the  tables  of  "  conductivity ;"  from 
their  relative  possession  of  the  characteristic  of  "  liability  to 
tarnish," — formation  of  more  or  less  soluble  salts ;  from  their 
possession  of  physical  integrity,  or,  liability  to  disintegration 
by  chemical  action ;  and  from  their  relative  capability  for  easy, 
and  consequently  more  perfect,  adaptation  to  cavity  walls. 

All  these  considerations  afford  subject-matter  for  thought  to 
the  plastic-filler,  while  the  gold-filler,  having  but  one  material 
to  think  upon,  can  think  of  but  one  thing  as  promising  success, 
viz.,  perfection  in  manipulation  ;  and  but  one  reason  can  present 
itself  to  his  mind  as  explanatory  of  failure,  which  is  "  defective 
manipulation." 

\Vith  thought  upon  the  points  which  I  have  presented,  there 
1ms  come  an  inquiry  into  the  varied  characteristics  of  all  the 
plastic  materials  that  are  subservient  to  the  saviny  of  teeth;  a 
systematic  investigation  of  their  behavior  under  all  possible 
conditions,  and  in  all  possible  positions,  in  the  mouth ;  a  prac- 
tical testing  of  the  harmonious  and  inharmonious  relations  ex- 
isting bet\veen  theory  and  experiment;  and  it  is  with  peculiar 
satisfaction  that  I  am  able  to  assert  the  singular  harmony  be- 
tween theory  and  practice  which  has  been  proven  to  exist  by 
the  tabulated  work  of  the  past  twenty  years. 

So  happily  successful  has  been  the  meeting  of  indications  by 
means  based  upon  the  principles  of  the  "  compatibility  "  theory, 
that  the  most  desperate  cases,  in  the  way  of  large  numbers  of 
dreadfully  inaccessible  cavities  filled  with  the  most  sensitive 
tissue,  and  in  teeth  of  the  softest  and  frailest  structure,  are  re- 
garded by  the  educated  plastic-fillers  with  perfect  equanimity, 
and  are  so  treated  and  filled  as  to  prove  eminentlv  satisfactory 
alike  to  patient  and  operator. 

Among  the  most  convincing  proofs  of  the  correctness  of  the 
theory  upon  which  the  plastic- fillers  base  their  choice  of  ma- 


186  PLASTICS    AND    PLASTIC    FILLING. 

terial  for  saving  teeth,  is  the  operation  under  discussion,  known 
as  "  guarding^" 

"  Guarding  "  is  the  placing  of  a  material  in  apposition  with 
the  cervical  wall  of  a  cavity  of  decay,  which  shall,  by  its  pos- 
session of  certain  physical  characteristics,  act  under  certain 
"law"  to  prevent,  in  greatest  degree,  the  recurrence  of  decay 
at  that  "  vulnerable  spot." 

It  is  to  the  plastic-fillers  of  the  present  day  that  dentistry  is 
indebted  for  the  utilization  of  tin-foil  as  a  guard  at  this  point. 
It  is  true  that  tin-foil  has  long  been  used  by  the  most  promi- 
nent gold-fillers  as  a  means  for  the  "  better  saving "  of  soft 
teeth,  but  its  advocacy  is  found,  by  reference  to  the  record,  to  be 
based  upon  the  greater  softness  of  the  material,  and  its  conse- 
quent easier  and  more  perfect  adaptation  to  the  cavity  walls. 

Thus  it  will  be  seen  that  the  manipulative  idea  was  ever  so 
prominent  as  to  be  the  only  thing  thought  worthy  of  attention. 

The  further  proof  that  this  is  so  may  be  found  in  the  con- 
stant repetition,  upon  scores  of  occasions,  that  this  soft  mate- 
rial was  only  intended  to  subserve  a  temporary  purpose ;  for  it 
is  everywhere,  and  at  all  times,  agreed  that  such  fillings  were 
to  be  allowed  to  remain  only  until  the  teeth  become  thoroughly 
calcified,  when  they  were  to  be  removed  and  PERMANENT  fillinys 
'of  GOLD  were  to  be  introduced! 

The  gold  work  upon  soft  teeth  has  been  founded  on  this  prin- 
ciple, and  has  been  practised  under  this  teaching  for  the  past 
fifty  years,  and  I  regard  it  as  unnecessary  that  I  should  waste 
one  word  in  reference  to  its  record. 

It  is  now  more  than  twenty  years  since  I  commenced  the  use 
of  tin-foil,  amalgam,  and  gutta-percha  as  guard-fillings  at  the 
cervical  walls ;'  not  because  they  were  soft  and  could  be  more 
perfectly  adapted  to  the  parietes,  but,  EMPIRICALLY,  because  I 
had  noted  that  fillings  made  from  these  materials  permitted 
occurrence  of  decay  less  promptly  than  did  gold,  even  when 
worked  by  the  best  manipulators  of  that  day  ;  not  with  the 
avowed  intention  of  removing  them  when  the  tooth -structure 
became  thoroughly  calcified,  but  with  the  intention  of  renew- 
ing them  when  decay  should  eventually  recur,  which  I  knew 
would  probably  be  the  case  at  some  future  time,  even  though 
the  recurrence  should  be  much  retarded. 


TECHNICALITIES.  187 

This,  which  at  that  time  was  empiricism,  has  become,  by  the 
adoption  of  the  Palmer  theory,  the  .strictest  following  of  science. 
Guarding  by  gutta-percha  or  amalgam  is  now  done  with  full 
reference  to  the  kno\yn  requirements,  the  physical  capabili- 
ties for  response  to  these  upon  the  part  of  the  filling  ma- 
terial, and  a  knowledge  of  future  probabilities  based  upon 
definite  data  which,  in  turn,  rest  upon  definite,  acknowledged 
"  law." 

In  cavities  which  are  accessible,  in  which  dryness  can  be 
attained  and  maintained,  in  which  lining  with  oxy-chloride  and 
final  filling  with  either  a  single  or  a  combination  amalgam  is 
thought  to  be  the  proper  practice,  a  guard  of  gutta-percha  is 
the  thing  indicated.  This  should  be  made  as  thin  as  possible 
consistent  with  certainty  that  it  thoroughly  protects  the  cervi- 
cal edge.  It  may  be  given  bulk  in  moderate  degree  within  the 
cavity,  and  worked  to  a  feather-edge  at  the  cervical  margin. 
It  is  better  that  it  protrude  a  little,  so  that  the  lining  and  final 
filling  having  been  accomplished,  and  the  amalgam  having  suf- 
ficiently set,  the  "  guard  "  may  be  neatly  trimmed  off  with  a 
heated  instrument.  This  insures  nice  adaptation,  desirable 
finish, 'and  perfect  protection. 

In  cavities  which  are  inaccessible  and  which  run  under  the 
gum,  and  in  which  it  would  be  impossible  to  maintain  dryness 
except  by  very  inflictive  methods, — dams,  darn-clamps,  or  dam- 
ligatures, — it  is  far  better  to  trust  to  submarine  amalgam.  This 
should  be  mixed  reasonably  plastic,  sufficiently  so  for  perfectly 
easy  manipulation,  and,  having  attained  what  dryness  may  be 
possible,  it  should  be  carefully  tapped  into  complete  apposition 
with  the  wall.  It  should  then  be  wafered,  that  firmer  consist- 
ence may  be  given  the  material.  It  should  be  built  up  de- 
cidedly thicker  than  a  guard  of  gutta-percha,  that,  when  set,  it 
may  be  trimmed  in  such  fashion  as  to  leave  a  neck  portion,  which 
may  be  utilized,  if  desired,  for  the  maintenance  of  dryuess,  by 
rubber-dam,  during  the  further  lining  or  filling  of  the  remain- 
ing portion  of  the  cavity. 

AVhen  fillings  of  gold  fail  at  these  "vulnerable  spots,"  guard- 
ing with  plastics  is  a  very  comfortable  and  satisfactory  method 
of  repairing  damages.  The  guarding,  even  in  this  compara- 
tively inaccessible  position, —  a  work  which,  with  gold,  would 


188  PLASTICS    AND    PLASTIC    FILLING. 

be  increasedly  difficult  and  painful, —  is  almost  invariably  less 
painful,  less  tedious,  less  expensive,  and  more  permanent  than 
was  the  original  operation. 

When  fillings  of  gutta-percha  fail  at  cervical  edges,  they 
may  readily  be  repaired  either  by  adding  gutta-percha,  which 
is  done  by  first  softening  the  edge  of  the  original  filling  by 
heated  instruments  and  then  joining  the  required  amount  of 
material  to  it,  or  by  grooving  the  cervical  margin  and  filling 
with  submarine  amalgam. 

If  amalgam  fillings  fail  at  cervical  edges,  it  is  only  needed, 
after  the  required  excavating,  that  a  guard  of  "  submarine " 
shall  be  cold-soldered  to  the  old  filling. 

As  conclusion  to  "  guarding,"  I  would  say  that  the  plastic 
school  of  dentistry  holds  to  the  view  that  the  "vulnerable 
spot "  is  found  to  be  located  at  the  cervical  edge,  not  from  any 
unusual  or  insurmountable  difficulty  which  precludes  the  possi- 
bility of  perfect  manipulation  of  material  at  this  point,  but  be- 
cause in  all  cases,  and  particularly  in  soft-tissued  teeth  contain- 
ing vital  pulps,  moisture  is  here  soonest,  most  constantly,  and 
most  abundantly  brought  in  contact  with  the  filling  material. 
It  holds  that  this  moisture  is  not  alone  that  from  the  outside, 
and  which  by  leakage  —  as  this  term  is  generally  understood  — 
might  notably  aid  "defective  manipulation"  in  its  work  of 
destruction ;  but  that  it  is  also  that  from  the  inside,  the  fluid 
which  is  essential  to  the  maintenance  of  vitality,  and  which  is 
thus  ever  present  in  living  tissue. 

It  holds  that,  as  this  moisture  is  gradually  brought  into  con- 
tact with  filling  material,  a  degree  of  electro-chemical  disinte- 
gration of  the  positive  substance  occurs,  which,  in  rapidity  and 
extent,  is  in  direct  ratio  with  the  existing  difference  in  poten- 
tial between  the  two  substances  in  contact. 

It  holds  that  the  difference  in  potential  between  gold  and 
tooth -bone  is  proven  to  be  very  great,  and  the  positivity  of 
tooth-bone  to  gold  is  equally  proven,  by  the  rapid  recurrence 
of  decay  at  this  cervical  margin,  when  cavities  in  teeth  of 
markedly  soft  structure  are  filled  with  gold. 

It  holds  that  the  lessening  difference  in  potential  between 
amalgam  and  tooth-bone  and  gutta-percha  and  tooth-bone  is 
proven  by  that  comparative  immunity  from  decay  which,  in 


TECHNICALITIES.  189 

direct  ratio,  is  found  to  result  when  cavities  in  soft  teeth  are 
filled  with,  or  guarded  by,  these  materials. 

It  holds  that  the  negativity  of  tooth-bone  to  filling  material 
is  proven  by  the  disintegration  of  the  fillings  made  with  zinc 
plastics ;  and  thus,  while  it  concedes  to  these  plastics  a  tooth- 
saving  power,  in  a  certain  sense,  it  nevertheless  denies  to  them 
the  ability  to  perform  "  guard  "  duty. 

Heating. — This  term  is  applied  to  various  processes  and  re- 
sults ;  but  its  exact  signification  in  any  given  case  is  under- 
stood from  the  connections  in  which  it  is  used;  thus  the  "heat- 
ing" of  gutta-percha  refers  to  its  softening  preparatory  to  using 
it  for  filling,  and  is  understood  to  be  a  process  which  must  be 
done  over  water  for  all  such  gutta-perchas  as  require  less  than 
210°  F.  for  proper  softening ;  and  equally  must  be  done,  and 
with  great  care,  upon  metal  plates  subjected  to  the  direct  flame 
of  gas  or  the  spirit-lamp  if  "high  heat"  gutta-percha  is  to  be 
employed. 

The  "  heating  "  of  instruments  is  understood  to  refer  to  the 
preparing  of  these  for  the  insertion  or  finishing  of  gutta-per- 
cha fillings  of  medium,  or  high-heat  grades,  a  process  which  is 
accomplished  by  a  tool-heater  or,  less  conveniently,  by  heating 
them  in  the  flame  of  a  spirit-lamp. 

The  "  heating  "  of  gutta-percha  for  testing  its  grade,  and  its 
relative  quality  as  pertaining  to  any  given  grade,  is  a  process 
which  is  conducted  on  a  gutta-percha  tester,  and  which  gives 
the  exact  thermometric  grading  of  different  samples  of  this 
filling  material. 

The  "  heating  "  of  zinc-phosphate  menstruum  refers  to  the 
melting  of  the  crystals,  a  process  which  requires  much  care 
that  it  be  done  without  permitting  the  boiling  of  the  syrupy 
fluid  which  results.  This  "  heating "  is  done  upon  a  small 
spoon  of  platinum  or  silver,  which  is  held  high  up  over  the 
flame  of  a  spirit-lamp,  that  the  melting  may  be  done  gradually, 
and  may  be  kept  perfectly  under  control. 

The  "  heating  "  of  a  zinc-phosphate  mix  is  that  generation 
of  heat  which  always  accompanies  the  union  of  the  menstruum 
and  powder.  It  is  of  very  varied  intensity  and  duration ;  but 
if  of  decided  intensity, —  sometimes  sufficient  to  burn, — •  or  of 
decided  length  of  duration,  it  is  a  fair  indication  of  question- 


190  PLASTICS    AND    PLASTIC    FILLING. 

able  material.  The  heating  of  a  good  zinc-phosphate,  though 
perceptible,  is  neither  intense  nor  of  long  duration. 

Lining. —  This  operation,  as  its  name  implies,  consists  in 
covering  the  inner  surface  of  cavity  walls  with  a  thin  stratum 
of  material  which  shall  subserve  the  purpose  either  of  pre- 
venting recurrence  of  decay ;  or  of  affording  support  to  un- 
yielding filling  material  which  would  otherwise  rest  upon  an 
unsubstantial  foundation;  or  of  preventing  discoloration  from 
filling  materials  liable  to  tarnish ;  or  of  precluding  the  possibil- 
ity of  clouding  from  leakage;  or  of  strengthening  frail  cavity 
walls. 

The  materials  used  for  lininy  are  varnishes  made  from  sanda- 
rac,  copal,  inspissated  Canada  balsam,  mastic,  etc.,  facing  amal- 
gam, oxy-chloride  of  zinc,  zinc-phosphate,  and  gutta-percha, 
either  in  solution  or  as  employed  for  filling. 

Linings  of  varnish,  facing  amalgam,  and  the  zinc  plastics,  par- 
ticularly the  zinc-chloride,  I  can  heartily  recommend,  as  I  have 
used  them  very  frequently,  and  for  many  years ;  but  the  linings 
of  gutta-percha  I  can  only  caution  against  as  unreliable.  The 
solutions  of  gutta-percha  have  a  worse  record  even  than  the 
thin  linings  of  gutta-percha  stopping,  and  this  is  needless,  for 
a  gutta-percha  foundation  has  ever  proven  insecure  in  the  ex- 
treme. 

Linings  of  varnish  are  indicated  in  shallow  cavities  where 
only  limited  undercuts  or  retaining-holds  can  be  obtained. 
They  should  be  permitted  to  dry  thoroughly,  and  will  then  be 
found  preservative  of  tooth-bone  and  preventive  of  discolora- 
tion. 

Linings  of  facing  amalgam  are  indicated  where  contour 
amalgam  is  to  be  used  for  building  portions  of  crowns  on  to 
remaining  portions  of  tooth-tissue  which  afford  but  slight  an- 
chorage for  the  filling.  In  these  cases  no  space  can  be  given 
to  zinc-plastics,  and  indeed  even  the  thin  space  occupied  by  a 
coating  of  varnish,  is  better  utilized  by  an  equal  thickness  of 
filling  material  to  which  attachment  may  be  made  for  the  con- 
touring. Facing  amalgam  meets  this  requirement. 

Linings  of  oxy-chloride  are  the  "  regular  thing."  In  all 
cases  of  deep  undercutting ;  in  all  cases  of  frail,  thin  walls ; 
in  all  cases  of  poor  tooth-structure ;  in  all  cases  of  discolored 


TECHNICALITIES.  191 

teeth ;  in  all  cases  of  marked  tendency  to  recurrence  of  decay, 
I  can  advise  a  good  oxy-chloride  lining. 

Linings  of  zinc-phosphate  are  yet  regarded  as  experimental. 
There  are  certain  qualities  pertaining  to  this  material  which 
render  it  more  desirable,  as  a  liner,  than  zinc-chloride.  These 
are  its  waxy  ductility  in  working,  which  permits  its  placing 
by  means  of  burnishers  instead  of  by  pelleting ;  its  perfect 
adaptation  to  cavity  walls  in  such  manner  as  to  be  easily  and 
nicely  brought  to  feather-edges  at  cavity  margins ;  the  rea- 
sonable strength  of  such  edges  when  compared  with  oxy- 
chlorides ;  the  greater  celerity  with  which  it  hardens,  and  its 
valuable  characteristic  of  non-shrinkage. 

All  these  give  to  zinc-phosphate  advantages  which  it  be- 
hooves us  to  utilize,  and  it  is  therefore  eminently  proper  that 
experimental  knowledge  as  to  its  maintenance  of  integrity  and 
permanence  of  utility  shall  be  obtained  as  promptly  and  as  posi- 
tively as  is  compatible  with  safety  to  such  teeth  as  require  such 
aid. 

Mixing. —  By  this  is  meant  the  final  uniting  of  two  prepara- 
tions, loth  of  which,  at  the  present  time,  are  compounds,  which 
mixture  results  in  a  material  which  is  either  directly  used  for 
some  process  connected  with  the  filling  of  a  cavity,  or  is  to  be 
utilized  for  this  purpose  by  some  other  process,  as  "  mixing " 
alloys  for  making  another  alloy. 

The  "  mixing  "  of  such  compounds,  as,  by  this  process,  make 
materials  for  capping  pulps,  lining  cavities,  or  filling  teeth,  is 
always  best  done  upon  a  glass-slab  with  a  spatula.  The  methods 
of  the  various  mixings  of  this  kind  have  been  given,  in  place, 
under  "oxy-chloride,"  "  <>xy-  sulphate,"  and  "zinc-phosphate;" 
but  it  remains  for  me  to  say  that  in  the  making  of  these  mix- 
ings there  is  the  greatest  possible  individual  difference. 

From  this  fact  it  is  impossible  that  all  should  attain  results 
which  shall  be  alike  valuable  or  satisfactory,  and  it  is  to  this, 
that  many  of  the  deficiencies  ascribed  to  plastic  materials  are 
due.  Every  operator  thinks  that  he  can  mix  any  plastic  with 
perfect  facility,  whereas,  the  truth  is  that  not  one  in  an  hundred 
can  make  the  most  advantageous  "mix"  with  any  of  them. 
They  are  either  mixed  too  thin  or  too  thick ;  too  slowly  or  too 
quickly;  the  menstruum  is  either  overloaded  or  undercharged; 


192  PLASTICS    AND     PLASTIC    FILLING. 

the  mix  is  taken  for  use  either  before  the  proper  time,  or  when 
the  setting  has  advanced  so  far  as  that  it  is  interfered  with,  and 
the  material  rendered  practically  valueless  in  its  introducing. 

NOTE. —  Some  time  since,  I  was  requested  by  a  manufacturer  to  tell  him  what 
I  thought  of  a  material  which  was  on  his  office-table.  I  poured  out  upon  a  slab 
a  little  of  the  fluid  and  a  portion  of  powder,  and  after  making  the  mix,  and  not- 
ing its  behavior,  told  him  it  was  a  good  oxy-chloride.  "  Do  you  think  it  good?  " 
said  he.  "Certainly,  quite  so,"  I  replied.  Upon  this  he  showed  me  a  letter 
with  which  the  package  had  been  returned ;  in  it  the  material  was  stamped  as 
perfectly  worthless,  and  a  very  emphatic  request  made  that  no  more  of  that 
kind  should  ever  be  sent  again.  After  some  weeks,  the  gentleman- — who  is  an 
expert  at  mixing — told  me  that  he  had  kept  the  material  in  his  office  until  he 
had  requested  quite  a  number  of  visiting  dentists  to  manipulate  it,  and  said  he, 
"  not  one  made  what  I  should  call  a  decent  mix." 

I  could  readily  appreciate  this,  for  my  own  office  has  been 
the  scene  of  numerous  very  funny  "mixes"  at  the  hands  of 
some  very  "eminent"  practitioners;  and  it  is  from  this  want 
of  knowledge  that  some  of  the  most  miserable  plastics  have 
secured  "testimonials"  which  will  in  the  near  future  be  as 
"peculiar"  as  are  zinc  alloys,  but  not  nearly  so  satisfactory. 

Such  "mix"  easily  ;  they  require  no  knowledge;  no  dexter- 
ity; no  promptness,  neither  proper  patience;  no  manipulative 
ability  for  their  using ;  they  require  nothing  but  "judgment." 

But  the  "mixing"  of  good  plastics  requires  everything  except 
judgment.  It  requires  thorough  knowledge  of  all  their  attri- 
butes during  combination ;  it  requires,  at  times,  exceeding 
dexterity ;  it  requires,  with  some,  a  promptness  which  can  be 
attained  but  by  few,  and  with  others  a  patience  which  is  not 
possessed  by  all. 

The  act  of  using  while  the  mix  is  setting  requires  peculiar 
manipulative  ability,  which,  while,  as  has  been  said,  it  can  be 
attained  by  a  larger  proportion  of  operators  than  can  attain  to 
the  most  excellent  manipulation  of  gold,  is,  nevertheless,  pos- 
sessed by  few,  if  any,  of  those  whose  energy  has  been  expended 
in  the  acquirement  of  the  ability  to  do  elegant  "gold  work.'' 

Beside  the  spatula  mixing  upon  the  glass  slab,  there  is  the 
"  alloy  mix  "  which  is  done  in  the  "  mixer  "  or  "  ager,"  as  the 
instrument  is  variously  styled,  and  by  means  of  which  some 
of  the  nicest  working  alloys  are  made  from  the  three  definite 
alloys  which  have  been  given  ;  of  these  I  may  mention  the 


TECHNICALITIES.  193 

"mix"  of  submarine  and  contour  alloys,  as  given,  for  a  usual  of 
remarkable  maintenance  of  color  on  articulating  faces  of  molars  ; 
the  "mix"  of  contour,  one  part;  facing,  two  parts;  as  a  very 
nice/row^  tooth  for  moderate  sized  cavities  in  bicuspids,  cuspids, 
and  incisors  ;  the  "  mix  "  of  submarine  and  contour,  equal  parts, 
where  a  tooth-preserving,  quick-setting,  contour-maker  of  good 
edge-strength  is  indicated  for  a  three-quarter  molar  crown  not 
decayed  as  low  as  the  gum,  etc. 

There  is  no  method,  of  which  I  am  cognizant,  that  will  so 
thoroughly  "mix"  alloys  as  the  revolving  cylinder.  This 
should  be  revolved  with  only  moderate  speed,  that  the  filings 
may  roll  together  over  each  other,  and  the  "  mixing"  should  be 
continued  for  a  sufficient  length  of  time  to  insure  completeness. 
This  for  a  small  lot  —  half  a  dozen  ounces  —  requires  about  an 
hour. 

Finally,  we  have  "heat  mixing,"  by  means  of  which  the 
powdered  silex  and  feldspar  is  mixed  with  the  molten  wax  and 
gutta-percha  base-plate. 

Pelleting  is  the  method  by  which  oxy-chloride  of  zinc  liu- 
i  ugs  are  best  placed  in  apposition  with  the  walls  of  cavities.  It 
is  done  by  first  rolling  several — five  or  six  —  small  pellets  of 
cotton  wool,  and  placing  the  thumb-pliers  and  an  appropriate 
plugging  instrument  in  readiness  for  use.  The  lining  material 
is  then  mixed  in  desired  amount  —  preferably  in  small  quan- 
tity—  and  is  taken  upon  the  end  of  the  spatula  and  placed 
approximately  in  position ;  one  of  the  cotton  pellets  is  then 
taken  in  the  thumb-pliers  and  with  it  the  lining  is  pushed  more 
accurately  as  desired ;  the  pellet  is  now  left  in  the  cavity,  and 
laying  down  the  pliers  the  plugging  instrument  is  used  to  com- 
press perfectly  the  pellet  and  subjacent  lining  material.  This 
pellet  is  now  removed  immediately,  before  the  setting  oxy- 
chloride  entangles  its  fibres,  and,  if  needed,  another  pellet  is 
pressed  into  position.  This  more  perfectly  dries  the  oxy- 
chloride,  and  accurately  places  any  portion  not  previously 
adapted.  Consecutive  quantities  of  lining  are  thus  placed  in 
position  accurately  and  neatly,  and  in  a  film  of  such  tenuity  as 
to  render  its  shrinkage  practically  nothing. 

Rulbiny. — This  term  is  used  with  reference  to  mortar-work, 
by  which  is  accomplished  the  pulverizing  of  ingredients,  the 
13 


194  PLASTICS    AND    PLASTIC    FILLING. 

compounding  of  powders,  or  the  fusing  of  filings  in  mercury 
as  they  are  rubbed  together. 

The  "  rubbing  "  of  the  frit  prior  to  compounding  the  pow- 
der of  oxy-chloride,  and  especially  the  "  rubbing  "  of  the  cal- 
cined sulphate  of  zinc  prior  to  compounding  the  powder  of  that 
pulp  protector,  are  matters  upon  which  depend,  essentially,  the 
quality  of  these  two  compounds. 

If  these  ingredients  are  not  thoroughly  "  rubbed,"  neither  of 
the  powders  will  permit  of  proper  mixing;  for  an  obdurate 
grit  will  consume  so  much  time  for  its  incorporation  with  the 
mass  as  to  either  deprive  it  of  the  value  of  a  portion  of  mate- 
rial or  necessitate  a  lengthy  spatulation  which  injures  seriously 
the  setting  qualities  of  the  "  mix." 

The  rubbing  of  filings  into  mercury,  for  the  making  of 
amalgam,  has  been  specially  referred  to  in  another  place.  The 
making  of  amalgam  is  best  accomplished  by  a  combination  of 
rubbing  and  palm-kneading ;  but  of  these  two  processes  the 
possibility  of  the  latter  depends  entirely  upon  the  proper  per- 
formance of  the  former.  It  has  been  taught  that  the  filings 
should  be  incorporated  with  the  mercury  with  a  certain  delib- 
eration and  yet  with  a  degree  of  celerity ;  but  that  a  fluidity 
of  the  first  portion  of  the  combined  metals  will  alone  permit 
of  the  making  of  a  plastic  mass  when  all  the  filings  are  in. 
Upon  the  proper  plasticity  of  the  amalgam,  as  the  result  of 
rubbing,  depends  the  possibility  of  its  subsequent  proper 
kneading. 

It  is  very  easy  to  add  a  little  more  filings  if  there  be  too 
great  plasticity;  and  it  is  equally  easy  to  add  a  little  more 
mercury  if  the  mass  is  too  hard,  or  even  crumbly;  but  this  is 
not  making  an  amalgam  which  will  "test"  as  would  a  properly 
made  material.  It  will  either  set  more  quickly  than  it  should, 
and  will  thus  be  less  homogeneous,  or  it  will  set  more  slowly, 
and  thus  be  less  dense.  Either  of  these  conditions  detracts 
from  its  edge-strength,  and  both  influence  shrinkage  and  -bulg- 
ing, and  consequently  crevicing.  In  short,  a  very  good  alloy 
may  thus  be  made  to  make  an  equally  ordinary  amalgam. 

From  time  to  time  various  materials  have  been  suggested  as 
desirable  to  use  in  connection  with  the  rubbing  of  the  anlalgam 
mass ;  some  for  the  purpose  of  producing  a  whiter  filling,  or 


TECHNICALITIES.  195 

one  which  would  better  maintain  its  whiteness ;  some  for  the 
purpose  of  making  a  quicker  union  of  the  ingredients ;  some 
for  the  purpose  of  attaining  greater  plasticity,  etc. 

These  additions  have  been  such  as  alcohol,  chloride  of  zinc, 
chloride  of  sodium,  common  chalk,  spirits  of  ammonia,  acids 
of  varied  kinds  and  strength,  from  strong  sulphuric  to  dilute 
acetic,  alum,  borax,  carbonate  of  soda,  carbonate  of  ammo- 
nia, etc. 

It  has  been  directed  to  use  these  in  their  ordinary  fluid  form, 
or  as  crystals,  or  as  dry  powders,  or  as  solutions ;  but  the  in- 
variable final  process  is  the  washing  out  of  the  adjunct  with  clear 
water. 

It  is  indisputable  that  some  of  these  additions  seem  to  produce 
desirable  results,  or  rather  that  they  produced  them  in  connec- 
tion with  the  amalgams  which  have  been  generally  employed  ; 
but  the  changes  in  alloy  formulae,  which  have  been  given,  se- 
cure results  which  far  more  than  equal  any  obtained  from  such 
means,  and  the  "  washing  "  which  they  necessitate  is,  of  itself, 
sufficient  to  condemn  them  all. 

AV////<<y  is  the  word  applied  to  the  hardening  of  all  plastic 
materials  used  for  filling  teeth,  or  in  connection  with  the  in- 
troduction of  fillings,  with  the  exception  of  such  as  contain 
gutta-percha  ;  these  are  said  to  "harden." 

The  setting  of  the  various  plastics  is  quite  peculiar,  each  ac- 
cording to  its  kind ;  thus,  "submarine  "  and  "  usual  "  amalgams 
set  with  medium  celerity.  "  Contour  "  amalgam  sets  with  re- 
markable rapidity ;  is  better  set  in  ten  minutes  than  ordinary 
amalgams  are  in  from  thirty  minutes  to  an  hour.  "Facing" 
amalgam  is  much  more  deliberate,  and  its  set  is  never  of  that 
firmness  and  density  which  are  so  essential  for  edge -strength, 
and  particularly  for  contouring  purposes. 

The  setting  of  zinc-sulphate,  while  dependent  upon  its  thin- 
ness or  thickness  of  mix  for  promptness  or  deliberation,  is, 
nevertheless,  always  quick  after  it  commences.  It  is  necessary 
that  the  material,  if  good,  be  mixed  tjuite  thin  or  milky,  in 
order  that  it  work  at  all  desirably  in  capping  or  protecting 
pulps;  for  if  anything  approaching  thick  consistence  is  at- 
tempted, it  will  set  not  only  before  it  can  be  used,  but  some- 
times even  before  it  can  be  well  mixed. 


196  PLASTICS    AND    PLASTIC    FILLING. 

The  setting  of  zinc-sulphate  is  also  peculiar  in  that  while  it 
sets  with  singular  hardness,  permitting  a  bright  polish,  it  never 
loses  its  decidedly  metallic,  astringent  taste,  but  responds  mark- 
edly to  a  slight  touch  of  the  tongue. 

It  is  this  property  which  seems  to  give  it  much  therapeutic 
value. 

The  setting  of  zinc-chloride  is  varied  both  by  the  composition 
and  the  freshness  of  the  powder,  and  also  by  the  strength  and 
condition  of  the  fluid.  For  good  settinj,  which  is  quite  delib- 
erate for  a  zinc  plastic,  the  powder  should  be  Avell  calcined  and 
reasonably  fresh.  When,  from  age,  the  mix  does  not  set  well, 
it  can  readily  be  made  to  do  so  by  re-calcining  the  powder  in 
a  crucible,  or,  frequently,  by  merely  placing  the  unstoppered 
bottle  of  powder  in  an  ordinarily  hot  oven  for  twenty  or  thirty 
minutes. 

The  setting  of  oxy-phosphate  is  slow  just  in  proportion  as  the 
compound  is  poor,  and  is  quick  equally  in  the  same  ratio.  In 
some  conditions  of  fluid,  syrup,  or  crystal,  the  mass  retains  its 
doughy  plasticity  for  many  minutes, — five  or  ten, — and  is  easily 
worked  and  moulded  during  nearly  all  this  time.  This  set  is 
very  deceptive ;  for  to  the  uninitiated  it  is  a  most  pleasing  and 
satisfactory  characteristic,  but  with  those  who  have  witnessed 
the  failing  of  fillings  made  from  such  material,  the  slow  set  is 
anything  but  desirable. 

In  other  conditions  of  fluid,  syrup,  or  crystal,  the  mass  sets 
with  instantaneous  rapidity,  and  then,  usually,  crumbles  into  a 
coarse  powder.  This  result,  though  proving  the  material  EITHER 
BADLY  MIXED  or  worthless,  is  better  for  the  operator  than  is 
the  slow  set ;  for  it  compels  him  to  mix  anew,  and  thus  defi- 
nitely settle  the  quality  of  his  plastic. 

The  setting  of  zinc-phosphate  is  quick,  within  reasonable 
bounds,  just  in  proportion  as  the  material  is  good ;  indeed,  the 
setting  of  a  good  zinc-phosphate  may  be  regarded  as  rather  too 
quick  to  be  considered  "  within  reasonable  bounds,"  for  it  is  so 
rapid  as  to  preclude  its  proper  working  by  any  except  dexterous 
manipulators. 

Those  who  work  slowly,  temperamentally  or  habitually,  can 
overcome  or  modify  this  rapidity  of  setting  by  mixing  "  soft ;  " 
but  the  set  cement  will  neither  be  so  hard  nor  so  durable  as  is 


TECHNICALITIES.  197 

that  which  is  mixed  with  proper  plasticity  and  manipulated 
with  proper  dexterity. 

Softening. — This  term  is  applied  equally  to  the  preparing  of 
filling  material  for  filling  purposes  or  for  the  rendering  of  filling 
material  easy,  or  comparatively  easy,  of  removal  from  cavities 
of  decay. 

The  softening  of  gutta-percha  stopping  is  done  in  two  ways, 
which  are  in  consonance  with  the  requirements  of  the  different 
grades  of  the  material.  "Low -heat"  and  "  medium -heat  " 
gutta-percha  are  softened  over  warm  or  boiling  water,  and 
should  never  be  softened  in  any  other  manner.  The  reason 
for  this  is,  that  the  proper  heat  can  be  secured  and  maintained 
more  perfectly  in  this  way  than  in  any  other.  There  is  also 
no  possibility  of  overheating,  and  thus  spoiling,  the  gutta- 
percha. 

High -heat  gutta-percha  is  softened  by  being  placed  on  a  me- 
tallic or  porcelain  plate,  and  subjected  to  heat  from  the  flame 
of  a  gas-jet  or  spirit-lamp.  Much  care  is  needed  for  this  soft- 
ening, as  the  heat  is  easily  raised  to  a  disintegrating  degree, 
240°  F.,  which  so  seriously  impairs  the  value  of  the  material 
as  to  render  it  practically  worthless. 

The  softening  of  a  gutta-percha  filling  for  the  purpose  of 
repairing,  adding  to,  or  removal  is  done  by  means  of  a  heated 
instrument, — usually  a  probe,  either  blunt  or  not  too  fine, — 
with  which  the  desired  result  is  readily  attained. 

The  softening  of  an  amalgam  filling  is  accomplished  by  drill- 
ing the  greatest  possible  number  of  small  drill-holes  in  the 
mass,  and  filling  these  with  mercury.  This  is  done  by  pouring 
;i  small  portion  of  mercury  into  the  glass  mortar,  and,  having 
taken  up  a  globule  of  the  metal  in  the  thumb-pliers,  placing  it 
upon  the  face  of  the  filling.  The  mercury  is  then  worked  into 
the  drill-holes  by  means  of  a  small  probe. 

In  a  short  time — thirty  minutes  or  so — the  mercury  will  have 
so  united  with  the  amalgam  as  to  permit  of  its  easy  drilling 
with  a  good,  sharp  burr-drill.  As  the  drilling  breaks  through 
column  after  column  of  the  mercurialized  amalgam,  the  filling 
will  become  more  and  more  readily  cut  into,  and  will,  not  in- 
frequently, break  up  into  several  pieces.  In  removing  these 
fillings,  it  is  better  that  the  cutting  in  two  —  halving  of 


198  PLASTICS    AND     PLASTIC    FILLING. 

them  —  should  be  systematically  aimed  at,  as,  this  having  been 
done,  it  is  usually  not  difficult  to  gently  force  the  separated 
halves  from  the  sides  of  the  cavity,  and  thus  take  them  away. 

Shrinkage. —  By  common  consent  and  habitual  usage,  the 
contraction  of  "  plastics "  is  called  shrinking ;  the  relative 
amount  of  contraction,  their  "degree  of  shrinkage;"  the  in- 
struments for  determining  this,  "shrinkers;"  and  the  other 
methods  for  attaining  the  same  results,  "  shrinkage  tests." 

For  ascertaining  the  shrinkage  of  amalgams,  the  three 
methods  which  have  been  adopted  as  reliable  are,  the  "  index 
micrometer,"  the  "  tube  test,"  and  micrometric  observation,  in 
regard  to  each  of  which  details  have  been  given. 

By  these  means  great  advance  has  been  made  in  diminishing 
the  degree  of  shrinkage  in  all  the  approved  amalgams,  while, 
at  the  same  time,  they  have  been  steadily  gaining  in  the  varied 
attributes  of  strength  of  edge,  rapidity  of  setting,  maintenance 
of  color,  plasticity,  and  compatibility  with  tooth-tissue. 

By  micrometric  observation  it  is  shown  that  shrinkage  of 
good  amalgam  has  been  reduced  to  less  than  l-1000th  of  an 
inch  in  an  ingot  of  two  micrometric  inches.  This  would  give 
as  the  shrinkage  of  a  quarter  of  an  inch  filling  the  very  small 
degree  of  the  nrioo  °f  an  inch. 

For  proving  the  shrinkage  of  gutta-percha,  it  is  usual  to  em- 
ploy the  "  tube  test,"  in  which  an  uncovered  tube  —  small  vial, 
made  of  extra  thick  glass  tubing  —  is  carefully  packed,  under 
visual  scrutiny,  with  the  preparation  to  be  sampled,  after  which 
aniline  ink  is  poured  into  the  vial.  In  a  short  time  the  shrink- 
age of  the  gutta-percha  is  proven  by  the  permeation  of  the 
purple  ink  between  the  filling  and  the  glass. 

Ivory  tubes  and  cups  have  been  used  for  this  purpose,  as 
imitating  closely  the  actual  tooth ;  in  these  the  shrinkage  of 
gutta-percha  —  both  red  and  white  —  is  demonstrated  to  be 
something  quite  notable,  as  leakage  takes  place  very  freely. 

The  shrinkage  of  oxy-chloride  of  zinc  is  well  demonstrated 
by  means  of  a  small  ring  of  glass  tubing  —  say  one-half  or 
three-quarters  of  an  inch  in  diameter.  This  being  packed  as 
for  rilling,  and  allowed  to  stand  for  a  few  days  —  three  to  five 
—  will  show  shrinkage  in  quantity. 

The  shrinkage  of  zinc-phosphate  is  tested  in  the  same  man- 


TECHNICALITIES.  199 

ner  as  is  that  of  zinc-chloride,  and  is  shown  to  be   merely 
nominal. 

Tapping. —  This  word,  used  in  dental  therapeutics  with  refer- 
ence to  entering  pulp  cavities  other  than  through  cavities  of 
decay,  is  employed  in  plastic  dentistry  with  reference  to  the 
packing  of  amalgam. 

For  many  years  it  has  been  directed  to  pack  amalgam  by 
rubbing  it  against  the  walls  of  cavities,  and  upon  such  portion 
of  amalgam  as  is  already  introduced.  It  is  most  conclusively 
demonstrated,  by  tube  packing,  that  this  is  a  very  unsatisfactory 
and  incomplete  method  of  inserting  amalgam.  It  is  therefore 
directed  that  it  be  done  by  "  tapping"  the  first  pieces  into  ap- 
position with  the  cavity  walls,  and  that  the  consecutively  in- 
troduced pieces  be  made  to  unite,  homogeneously,  with  those 
previously  introduced, by  "tapping." 

Tapping  consists  in  delivering  light  blows,  from  the  appro- 
priate filling  instruments,  upon  the  amalgam  after  it  has  been 
crushed  into  approximate  position  and  apposition.  This  "  tap- 
ping "  is  not  to  be  done  with  mallets,  either  hand,  automatic,  or 
electric,  as  a  different  kind  of  blow  from  any  so  given  is  far 
preferable.  The  "tap  "  from  the  filling  instrument  —  the  same 
used  for  crushing  —  is  a  mingled  push  and  blow,  which  is  soon 
acquired,  and  is  as  promptly  recognized  as  very  efficient  in  pro- 
ducing admirable  results. 

Testing. —  This  word  is  used  in  reference  to  an  immense  line 
of  work  which  has  been  required  by  the  exigencies  of  develop- 
ment. 

It  is  such  work  as  has  been  but  little  demanded  in  connec- 
tion with  the  use  of  gold,  for  the  "  testing  "  of  this  material  is 
confined  to  its  manipulation  during  insertion,  while  the  "tests" 
which  have  been  applknl  to  it  meet  with  no  concurrence  from 
a  plastic-filler  as  to  their  value.  The  amount  of  any  material 
packed  in  a  cavity  —  decided  by  its  weight  —  is  held  by  the 
plastic-filler  as  of  little,  if  any,  import  as  regards  the  tooth - 
saving  value  of  the  filling. 

The  solidity  of  any  filling,  even  of  gold,  is  regarded  by  the 
plastic-filler  as  no  criterion  of  the  real,  tooth-saving  worth  of 
the  work. 

Even  the  apposition  of  the  filling  material  to  the  walls  of 


200  PLASTICS     AND     PLASTIC    FILLING. 

the  cavity  is  viewed  by  the  plastic-filler  from  his  peculiar  stand- 
point ;  for  he  notes  the  constant  failure  of  the  gold  fillings  with 
their  elegant  microscopic  adaptation,  and  the  wonderful  preser- 
vation afforded  by  gutta-percha  with  its  known  deficiency  in 
that  respect ;  thus  it  is  that  the  circumscribed  line  of  work  in 
the  "  test "  packing  of  gold,  surrounded  as  it  is  with  the  high- 
sounding  epithets  of  "  artistic,"  "  elaborate/'  "  ideal,"  etc.,  is 
viewed  by  the  plastic-worker  with  mingled  wonder  and  amuse- 
ment, and  is  thought  to  have  but  little  "  weight,"  less  "  solid- 
ity," and  no  appreciable  "  apposition  "  to  the  great  question  of 
tooth-salvation. 

The  "  test  work  "  of  plastics  is  the  natural  result  of  a  multi- 
plicity of  materials  and  of  the  desired  modifications  in  connec- 
tion with  numerous  compounds.  Not  alone  have  the  attributes 
of  silver,  tin,  gold,  copper,  zinc,  mercury,  gutta-percha,  oxide 
of  zinc,  sulphate  of  zinc,  chloride  of  zinc,  nitrate  of  zinc, 
borate  of  soda,  the  acids  of  phosphorus,  alcohol,  the  gums  of 
mastic,  sandarac,  copal,  caoutchouc,  and  acacia,  oxide  of  tin, 
wax,  sulphite  of  lime,  feldspar,  and  silex  to  be  considered,  but 
the.  endless  variety  of  composition  in  which  these  ingredients 
may  be  advantageously  employed ;  and  when  to  these  are 
added  the  "  questionables,"  of  doubtful  value,  but  which  have 
claims  that  entitle  them  to  attention,  such  as  antimony,  bis- 
muth, cadmium,  palladium,  alumina,  gypsum,  chalk,  alum, 
kaolin,  and  quick-lime,  is  it  strange  that  the  word  "  testing '' 
has  a  meaning  for  the  worker  in  plastics  beside  which  the  repe- 
titions that  have  formed  the  "  discussions "  of  dental  societies 
for  the  past  twenty  years  seem. like  time-wasting  trifling? 

On  the  one  hand,  we  have  the  rehash  of  methods  and  manip- 
ulations which  have  resulted  in  making  it  questionable  whether 
the  title  of  "permanent  denture"  is  most  appropriately  applied 
to  natural  or  artificial  teeth !  while  on  the  other,  we  have  that 
work  which  by  "  testing  "  has  resulted  in  materials,  methods, 
and  manipulations  which  fairly  bid  defiance  to  the  ravages  of 
caries,  and  make  of  the  frailest  and  softest  teeth  wonderfully 
"permanent  dentures." 

In  a  paper  which  was  read  before  the  American  Dental  As- 
sociation, Niagara  Falls,  August,  1878, — not  published  in  the 
Transactions, — reference  was  made  to  the  statement,  from  one 


TECHNICALITIES.  201 

of  those  to  whom  students  of  dentistry  look  for  instruction, 
that  plastic  work  was  "  guess  work.'1'1  To  this  1  replied  that 
"so  far  from  being  ' guess  work,'  we  have  a  range  of  'tests' 
which  tell  us  very  well  what  we  may  expect  of  any  material 
under  given  conditions.  These  are  such  as  strength  test,  edge 
test,  setting  test,  shrinkage  test,  expansion  test,  color  test,  heat 
tests  (wet  and  dry),  leakage  test,  fretting  test  (for  probable 
wear),  acid  test,  alkali  test,  conduction  test  (electrical  and  ther- 
mal), and  finally  the  oral  test,  which  decides 'the  compatibility 
of  materials  with  tooth-bone  and  their  behavior  in  the  oral 
fluids  and  under  oral  influences. 

"  By  means  of  these  tests  we  are  enabled  to  make  a  choice  of 
material  to  meet  the  varied  indications  that  constantly  present  in 
practice,  which,  to  our  apprehension,  approaches  to  SOMETHING 

LIKE    SCIENCE. 

"  It  is  by  these  means  that  we  frequently  combine  two,  three, 
four,  or  more  different  materials  in  the  filling  of  one  cavity, 
each  of  which  best  subserves  its  purpose  in  its  appropriate  po- 
sition, and  insures  an  operation  which  for  comfort,  beauty,  and 
permanency  can  in  no  other  ivay  be  equalled." 

All  this  is  so  entirely  at  variance  with  that  stereotyped  prac- 
tice which  it  is  the  duty  of  the  publishing  committee  to  place, 
year  after  year,  before  the  profession,  that  it  seems  "  reasonable 
and  consistent  "  it  should  be  deemed  imperative  to  suppress  it. 

This  alone  would  doubtless  have  been  sufficient  to  decide 
the  action  of  any  dental  publication  committee,  but  when  to  it 
was  added  the  assertion  that  Plastic  Dentistry  "is  even  now  a 
very  well  worked-up  specialty  of  our  profession  ;  one  that  is  so 
little  knou'u  as  scarcely  to  be  mentioned  except  with  contempt  or 
disapprobation  from  the  lecture  stand,  AXD  YET  one  ichich  can 
/(<:>/'_•  take  any  denture  so  forlorn  as  tn  In'  HOPELESSLY  abandoned 
by  the  BEST  GOLD  OPERATOR  in  tin'  vurlil  and  make  of  it  a 

COMFORTABLE,  SATISFACTORY,  and    BEAUTIFUL    SUCCESS."    then 

suppression  of  such  a  damaging  assertion,  particular!}'  if  it  was 
in  the  least  degree  probable  that  it  could  be  sustained,  became 
a  duty  which,  in  its  magnitude,  was  simply  overwhelming. 

What  an  extraordinary  thing  is  the  sense  of  duty  ! 

I  have  felt  it  my  duty  to  place  these  statements  before  my 
professional  brethren  because  they  have  all  been  made  as  the 


202  PLASTICS    AND    PLASTIC    FILLING. 

results  of  long  and  thorough  "testing  ;"  because  I  am  conversant 
with  the  continued,  persistent  work  which  has  been  required  to 
do  this ;  because  I  know  of  the  earnest  interest  with  which  the 
work  has  been  done ;  because  I  know  of  the  thousands  of 
patients  who  have  realized  the  benefits  of  the  work;  because  I 
know  of  what  I  speak — that  it  is  capable  of  demonstration 
that  it  is  true ;  because  I  feel  that  in y  profession  needs  it ;  be- 
cause I  feel  that  suffering  humanity  needs  it ;  because  I  feel  that 
the  cause  of  progress  demands  it. 

Thus  it  is  that  in  my  "decision*'  I  am  "actuated  by  personal 
prejudice."  I  do  consider  the  statements  of  "  sufficient  value  "  to 
warrant  their  presentation  ;  I  am  "  influenced  by  "  most  decided 
"  opposition  to  the  doctrines  advanced  "  in  the  usual  dental  con- 
tributions ;  and  I  also  am  "  governed  solely  by  a  sense  of  duty" 

Trimming  refers  to  the  cutting  away  or  removing  of  surplus 
filling  material.  In  plastic  filling,  it  is  almost  universally  the 
case  that  a  superabundance  of  material  is  introduced.  This  is 
due  to  the  fact  that  no  more  time,  if  as  much,  is  required  to 
more  than  fill  any  cavity  than  would  be  needed  for  the  accu- 
rate filling  of  the  same.  It  is  also  found  to  be  advantageous 
that  an  ample  amount  of  filling  be  given  for  final  shaping.  It 
is  less  difficult  to  remove  surplus  than  it  is  to  add  on.  The 
materials  are  comparatively  inexpensive,  and  thus  "  waste  " 
does  not  involve  much  "loss."  The  removal  of  surplus  does 
not  necessitate  inflictive  or  disagreeable  instrumentation,  such 
as  hand-filing,  chiselling,  stoning,  etc.,  as  is  the  case  with  gold. 

In  trimming  amalgam  fillings,  all  grades  of  tool-edge  are  not 
only  admissible  but  desirable,  from  the  sharp  edge  of  the 
"  trimmer "  to  the  absolutely  round  edge  of  the  curved  bur- 
nisher. This  latter  is  particularly  useful  and  non-inflictive  for 
trimming  the  fillings  and  making  smooth  adaptation  of  filling 
with  cavity  edge  below  the  gum,  especially  on  buccal  faces; 
while  the  thin-edged,  paper-like  separators  are  admirably  cal- 
culated for  trimming  between  teeth. 

For  trimming  fillings  of  gutta-percha,  I  use  exclusively 
heated  instruments,  several  of  which  being  heated  at  once  upon 
the  "tool-heater,"  it  is  easy  to  adapt  varied  shapes  to  varied 
requirements. 

For   trimming  zinc-phosphate  fillings,  sharp-cutting   instru- 


TECHNICALITIES.  203 

ments  are  required,  such  as  knife-edged  trimmers,  burrs,  and 
files.  These  should  be  kept  perfectly  dry  or  thoroughly  wet, 
as  by  these  means  the  filings  or  cuttings  are  either  dry  powder, 
which  can  be  blown  away,  or  make,  by  free  dilution,  a  milky 
fluid  which  does  not  seriously  clog  either  burr  or  file. 

Trunnioning. — It  is  by  this  operation  that  amalgam  buffers 
of  all  sizes  are  retained  firmly  in  position,  when  they  do  double 
duty  in  that  they  prevent  wear  from  attrition  upon  gutta- 
percha  guards,  and  disintegration,  by  fluids  of  the  mouth,  of 
oxy-chloricle  linings.  Suppose  a  cavity  in  a  molar  or  bicuspid, 
mesial  or  distal,  reaching  up  to  or  under  the  gum,  nearly  into 
the  pulp,  extending  partially  over  the  articulating  face  of  the 
tooth,  and  having  very  frail,  thin  walls  both  buccally  and 
lingually.  This  condition  is  frequently  found  in  bicuspids  of 
soft  structure  which  have  been  filled  repeatedly  with  gold.  In 
such  the  cervical  edge  is  first  guarded  by  a  layer  of  gutta- 
percha,  which  is  neatly  extended  far  enough  into  the  cavity  to 
prevent  pulp  irritation  from  conduction  after  filling,  and  from 
zinc-chloride  irritation  during  lining.  The  cavity  is  now  lined 
buccally  and  lingually  with  oxy-chloride  of  zinc,  which  is  al- 
lowed to  set  thoroughly,  covering  it  temporarily  with  "tempo- 
rary stopping  "  for  an  hour  or  two,  or  a  day  or  so  if  more  con- 
venient. 

When  the  zinc  lining  is  perfectly  set,  an  indentation  or  pit 
is  drilled  into  each  side  of  it,  buccal  and  lingual,  as  large  as  is 
consistent  with  strength ;  a  contour  amalgam  filling  is  now 
made,  which  by  entering  the  drill-pits  becomes  held  by  trun- 
nions, and  thus  solidly  maintains  its  position. 

\V<iferiny. — Upon  the  intelligent  utilizing  of  this  process 
depends  largely  the  comfort,  satisfaction,  and  success  of  amal- 
gam work.  It  consists  of  making  wafers  of  small  portions  of 
amalgam,  and  using  them  for  the  purpose  of  increasing  the  con- 
sistence of  amalgam  which  has  been  introduced  soft  for  some 
specific  object,  as  prevention  of  pulp  irritation,  prevention  of 
too  severe  impinging  upon  exquisitely  sensitive  or  heavily  de- 
calcified dentine,  or,  to  facilitate  its  insertion  into  some  exceed- 
ingly inaccessible  location;  or  to  increase  normal  consistence  of 
already  introduced  amalgam  for  the  purpose  of  hastening  set- 
ting, and  thus  permitting  prompt  continuance  of  work,  as  in 


204  PLASTICS    AND    PLASTIC    FILLING. 

building;  or  for  the  hardening  of  the  face  of  a  filling,  that  the 
work  of  finishing  may  be  facilitated,  while  at  the  same  time 
an  increase  of  edge-strength  and  a  whiter  face  may  be  insured. 

The  icafer  is  made  by  taking  a  small  portion  of  the  amalgam 
and  folding  it  in  a  piece  of  "chamois-skin;"'  the  chamois  is  now 
twisted  so  as  to  .secure  the  amalgam  and  prevent  such  escape  of 
mercury  from  squeezing,  as  may  permit  of  its  again  being 
taken  up  from  contiguity  by  the  wafer. 

The  squeezing  of  the  amalgam  should  be  done  with  large, 
strong  pliers  —  as  illustrated  —  made  expressly  for  this  purpose; 
these  are  about  seven  inches  in  length,  with  flat,  round-edged 
jaws  —  so  as  not  to  cut  the  chamois-skin  —  and  are  properly 
adapted  to  thorough  squeezing  with  the  expenditure  of  com- 
paratively little  force. 

This  is  an  important  consideration,  for,  with  ordinary  sized 
pliers,  either  the  squeezing  would  be  insufficient,  or  the  force 
required  would  be  inflictive  to  the  hand.  The  difference  in  the 
physical  characteristics  of  wafers  made  by  using  the  ordinary 
pliers  and  those  made  by  the  appropriate  pliers  can  only  be 
realized  by  comparison  of  the  two  results,  and  the  success  of 
wafering  is  widely  different  when  done  by  thoroughly -squeezed 
instead  of  half-squeezed  "  wafers." 

Washing. —  I  have  merely  introduced  this  term  that  I  may 
once  more  enter  a  protest  against  the  process  to  which  it  refers. 
Every  experiment  points  to  the  inutility  of  "  washing  "  amal- 
gam ;  every  experiment  indicates  that  it  is  worse  than  useless; 
that  it  is  detrimental.  It  is  conceded  that  fillings  made  with 
submarine  amalgam  would,  theoretically,  be  better  made  if  done 
dry ;  while  the  fact  that  good  results  follow  wet  work  is  only 
urged  in  the  humane  effort  to  accomplish  respectable  tooth- 
saving  without  the  necessity  for  dire  infliction.  Therefore, 
I  should  condemn  any  process,  in  connection  with  the  making 
of  amalgam,  which  entailed,  as  a  part  of  its  performance,  the 
washing  of  the  material. 

Weighing. —  In  plastic  filling  this  word  refers  only  to  the 
manner  of  determining  the  relative  quantities  of  mercury  and 
filings  required  for  the  making  of  any  definite  amalgam  ;  or 
for  the  modifying  of  the  known  best  make  of  any  given  amal- 
gam that  exigencies  may  be  accurately  met. 


TECHNICALITIES.  205 

I  think  it  sufficient  to  prove  the  importance  which  I  attach 
to  the  weighing  of  the  ingredients  for  making  amalgam,  when 
I  state  that,  with  the  daily  experience  which  I  have  had  for 
nearly  twenty-five  years,  I  never  make  amalgam  without  weigh- 
ing the  proportions. 

Recognizing  completely  the  necessity  for  accurate  compound- 
ing in  the  obtaining  of  definite  results,  I  know  that  /  cannot 
even  closely  approximate  the  desired  amounts  of  mercury  and 
filings,  and  I  further  know  that  if  I  could  it  would  not  be  suffi- 
ciently accurate  for  my  purpose. 

Upon  very  many  occasions,  I  have  requested,  from  those 
who  claimed  ability  to  "judge  "  with  "reasonable  accuracy  "  in 
this  apportionment,  demonstrations  of  their  skill,  and  I  think 
the  sequence  has  been,  almost  universally,  a  determination  upon 
the  part  of  the  experimenters  to  weigh  their  proportions  in 
future. 

The  fact  is,  no  one  can  secure  anything  more  than  a  very 
rude  approach  to  the  required  amounts  of  mercury  and  filings 
for  the  making  of  amalgam,  if  this  is  done  by  the  "judgment " 
method ;  whereas,  by  the  weighing  method,  one  can  soon  be- 
come so  expert  as  to  prognose  the  consistence  or  plasticity 
which  will  pertain  to  nearly  every  "  make  "  of  amalgam  mass 
before  it  is  rubbed, 

This  is  what  is  required ;  for  thus  it  is  that  the  proper  plas- 
ticity for  meeting  special  indications  is  given  any  appropriate 
selection  of  amalgam ;  thus,  a  submarine  mass,  which  is  to  be 
used  in  an  accessible  cavity  upon  the  buccal  face  of  a  lower 
first  molar,  would  naturally  be  made  of  firm,  workable  con- 
sistence ;  while  the  same  alloy  would,  as  appropriately,  be  made 
into  an  amalgam  of  soft  plasticity,  if  the  cavity  to  be  filled  were 
exceedingly  inaccessible,  and  was  possessed  of  frail  walls,  spot- 
tings  of  excessively  sensitive  dentine,  or  other  like  complica- 
tions. 

By  weighing,  all  these  important  considerations  are  promptly, 
neatly,  and  accurately  met ;  and  I  think  that  years  of  practice 
will  only  serve  to  demonstrate  to  others  that  which  has  been 
demonstrated  to  me,  viz.,  by  no  other  method  than  WEIGHING, 
can  satisfactory  making  of  amalgam  be  accomplished. 

I  will  repeat,  that  the  iceighing  is  not  to  be  done  with  weights. 


206  PLASTICS    AND    PLASTIC    FILLING. 

but  by  weight ;  and  I  would  say,  that  although  the  making  of 
amalgam  from  reliable  alloys  is  always  done  with  an  approxi- 
mately horizontal  scale  beam,  yet,  to  the  expert,  the  slight  de- 
viations from  this  are  the  means  by  which  he  uniformly  accom- 
plishes any  desired  modification. 

Whitening. —  This  term  is  applied  alike  to  teeth  and  to 
fillings.  In  plastic  dentistry,  the  "  bleaching "  of  teeth  is 
ignored  as  a  detrimental  and  non-compensating  process,  and 
consequently  the  word  has  become  obsolete. 

In  the  article  on  oxy-chloride  of  zinc,  its  use  as  a  whitener 
of  teeth  has  been  explained,  and  reference  has  been  made  to 
the  permanence  which  attaches  to  this  restoration  of  color. 

In  the  article  on  "  insertion  of  amalgam,"  the  peculiar  method 
of  white  finishing  has  been  described;  but  as  this  was  then  only 
one  point  among  many,  and  as  considerations  of  beauty  have 
obtained  notable  prominence  in  "  plastic- work "  ever  since 
reaching  conclusions  upon  the  practical  problem  of  tooth-salva- 
tion, I  regard  it  as  proper  to  direct  attention  again  to  the  fin- 
ishing of  amalgam  fillings. 

After  the  required  ten  or  fifteen  minutes  of  setting,  an  amal- 
gam filling  may  receive,  if  needed,  its  accurate  contouring  by 
trimming,  and  should  then  have  its  second  finishing  from  the 
piece  of  pine  stick  as  described  in  the  article  referred  to. 

This  finishing  results  in  a  white  face,  which,  though  yet  of 
comparatively  coarse  grain,  is  nevertheless  much  finer  in  ap- 
pearance than  was  the  grain  given  by  the  first  smoothing. 
Again,  ten  minutes  or  so  should  be  given  for  further  setting, 
when  the  filling  may  be  finally  finished.  The  final  finish  is 
given  by  the  soft  pine  stick,  but  it  is  sometimes  found  necessary 
to  add  to  this  a  little  finely  leviyated  pumice.  This  is  made  In- 
putting in  a  basin  part  filled  with  water  a  small  quantity  of  such 
pulverized  pumice  as  is  usually  sold.  It  is  then  thoroughly 
stirred  up,  and  allowed  to  settle  perfectly.  The  clear  Avater, 
\vith  the  floating  impurities,  is  then  poured  off.  The  basin  is 
again  partially  filled  with  water,  and  the  pumice  again  thor- 
oughly stirred  up.  This  is  then  allowed  to  settle  for  &few 
seconds  —  four  or  five  —  when  the  milky  fluid  is  poured  off,  and 
the  fine  pumice  contained  in  it  is  permitted  to  settle  until  the 


CONCLUSION.  207 

water  is  again  perfectly  clear.  The  clear  water  is  poured  oil', 
and  the  remaining  fine  sediment  is  dried  for  use. 

When  the  final  finish  is  given,  it  will  be  noted  that  the  most 
decided  whitening  is  accomplished  by  smoothing  the  face  of  the 
filling  in  a  downward  or  upward  direction, —  as  it  is  in  an  upper 
or  lower  tooth, —  and  not  across  the  filling  disto-mesially. 

This  method  of  finishing  leaves  a  striated  surface,  which, 
though  microscopic  in  the  fineness  of  its  markings,  yet  pre- 
sents a  succession  of  faces  upon  which  the  light  impinges  di- 
rectly, and  by  which  a  reflected  whiteness  is  given  to  the  filling. 


CONCLUSION. 

WITH  this  I  am  permitted  to  see  the  end  of  a  work  which 
was  commenced  a  quarter  of  a  century  ago.  Its  possibilities 
were  then  discussed,  its  probabilities  foretold,  but  the  view  of 
its  realization — then,  to  a  few,  an  ideal  of  the  far-off  future  — 
has  been  granted  to  me  alone. 

Although  it  is  with  grateful  satisfaction  that  I  now  contem- 
plate the  gradual  development  of  that  which  has  been  the 
medium  for  so  much  alleviation  to  suffering,  so  much  bestowal 
of  long-enduring  comfort,  and  such  incontestably  beneficial  re- 
sults, it  is  yet  with  mingling  of  regret  and  pleasure  that  I  cast 
it  forth  to  do  battle  in  the  struggle  for  professional  place  and 
precedence. 

I  shall  regret  to  see  it  frowned  upon ;  I  shall  regret  to  see  it 
misrepresented,  and  yet  I  can  but  know  that  it  must  meet  with 
the  common  reception  of  those  numerous  predecessors  which 
have  waged  war  against  "  accepted  doctrines  ; "  but  it  is  to  me 
a  pleasure  indeed  that  I  am,  even  yet,  afforded  ample  oppor- 
tunity for  the  practical  demonstration  of  the  truths  of  its  teach- 
ings, and  that  strength  is  yet  given  me  to  raise  my  voice  in  its 
defence. 

I  ask  for  it  a  serious,  thoughtful  consideration,  and  sincerely 
hope  that  much  good  may  come  of  it. 


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